MLECO-3096: Removing data_acq and data_psn

Further to the HAL refactoring done in previous commits,
this CR simpifies HAL by removing data_acq and data_psn
"modules". The associated function pointers have been
removed.

Change-Id: I04c194c08dfe0aff98ce4e0f0f056bac254c137d
Signed-off-by: Kshitij Sisodia <kshitij.sisodia@arm.com>

28 files changed, 236 insertions, 475 deletions

diff --git a/source/application/main/Main.cc b/source/application/main/Main.cc
index 8ed9c5a..e27d5b5 100644
--- a/source/application/main/Main.cc
+++ b/source/application/main/Main.cc
@@ -42,12 +42,10 @@ static void print_application_intro()
 int main ()
 {
     hal_platform    platform;
-    data_acq_module dataAcq;
-    data_psn_module dataPsn;
     platform_timer  timer;
 
     /* Initialise the HAL and platform. */
-    hal_init(&platform, &dataAcq, &dataPsn, &timer);
+    hal_init(&platform, &timer);
 
     if (0 == hal_platform_init(&platform)) {
         /* Application information, UART should have been initialised. */
diff --git a/source/application/main/UseCaseCommonUtils.cc b/source/application/main/UseCaseCommonUtils.cc
index d439446..340a767 100644
--- a/source/application/main/UseCaseCommonUtils.cc
+++ b/source/application/main/UseCaseCommonUtils.cc
@@ -36,12 +36,7 @@ void DisplayCommonMenu()
     fflush(stdout);
 }
 
-
-
-
-bool PresentInferenceResult(
-    hal_platform &platform,
-    const std::vector<arm::app::ClassificationResult> &results)
+bool PresentInferenceResult(const std::vector<arm::app::ClassificationResult> &results)
 {
     constexpr uint32_t dataPsnTxtStartX1 = 150;
     constexpr uint32_t dataPsnTxtStartY1 = 30;
@@ -51,7 +46,7 @@ bool PresentInferenceResult(
 
     constexpr uint32_t dataPsnTxtYIncr = 16;  /* Row index increment. */
 
-    platform.data_psn->set_text_color(COLOR_GREEN);
+    hal_lcd_set_text_color(COLOR_GREEN);
 
     /* Display each result. */
     uint32_t rowIdx1 = dataPsnTxtStartY1 + 2 * dataPsnTxtYIncr;
@@ -66,13 +61,13 @@ bool PresentInferenceResult(
                 std::to_string(results[i].m_labelIdx) +
                 " (" + std::to_string(results[i].m_normalisedVal) + ")";
 
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                 resultStr.c_str(), resultStr.size(),
                 dataPsnTxtStartX1, rowIdx1, false);
         rowIdx1 += dataPsnTxtYIncr;
 
         resultStr = std::to_string(i + 1) + ") " + results[i].m_label;
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                 resultStr.c_str(), resultStr.size(),
                 dataPsnTxtStartX2, rowIdx2, 0);
         rowIdx2 += dataPsnTxtYIncr;
@@ -134,12 +129,12 @@ bool RunInference(arm::app::Model& model, Profiler& profiler)
     return runInf;
 }
 
-int ReadUserInputAsInt(hal_platform& platform)
+int ReadUserInputAsInt()
 {
     char chInput[128];
     memset(chInput, 0, sizeof(chInput));
 
-    platform.data_acq->get_input(chInput, sizeof(chInput));
+    hal_get_user_input(chInput, sizeof(chInput));
     return atoi(chInput);
 }
 
@@ -181,7 +176,6 @@ void DumpTensor(const TfLiteTensor* tensor, const size_t lineBreakForNumElements
 bool ListFilesHandler(ApplicationContext& ctx)
 {
     auto& model = ctx.Get<Model&>("model");
-    auto& platform = ctx.Get<hal_platform&>("platform");
 
     constexpr uint32_t dataPsnTxtStartX = 20;
     constexpr uint32_t dataPsnTxtStartY = 40;
@@ -192,12 +186,12 @@ bool ListFilesHandler(ApplicationContext& ctx)
     }
 
     /* Clear the LCD */
-    platform.data_psn->clear(COLOR_BLACK);
+    hal_lcd_clear(COLOR_BLACK);
 
     /* Show the total number of embedded files. */
     std::string strNumFiles = std::string{"Total Number of Files: "} +
                                std::to_string(NUMBER_OF_FILES);
-    platform.data_psn->present_data_text(strNumFiles.c_str(),
+    hal_lcd_display_text(strNumFiles.c_str(),
                                          strNumFiles.size(),
                                          dataPsnTxtStartX,
                                          dataPsnTxtStartY,
@@ -210,7 +204,7 @@ bool ListFilesHandler(ApplicationContext& ctx)
         for (uint32_t i = 0; i < NUMBER_OF_FILES; ++i, yVal += dataPsnTxtYIncr) {
 
             std::string currentFilename{get_filename(i)};
-            platform.data_psn->present_data_text(currentFilename.c_str(),
+            hal_lcd_display_text(currentFilename.c_str(),
                                                  currentFilename.size(),
                                                  dataPsnTxtStartX, yVal, false);
 
diff --git a/source/application/main/include/UseCaseCommonUtils.hpp b/source/application/main/include/UseCaseCommonUtils.hpp
index 7f5dde6..9b6d550 100644
--- a/source/application/main/include/UseCaseCommonUtils.hpp
+++ b/source/application/main/include/UseCaseCommonUtils.hpp
@@ -31,12 +31,10 @@ void DisplayCommonMenu();
   /**
    * @brief           Presents inference results using the data presentation
    *                  object.
-   * @param[in]       platform    Reference to the hal platform object.
    * @param[in]       results     Vector of classification results to be displayed.
    * @return          true if successful, false otherwise.
    **/
-bool PresentInferenceResult(hal_platform& platform,
-                            const std::vector<arm::app::ClassificationResult>& results);
+bool PresentInferenceResult(const std::vector<arm::app::ClassificationResult>& results);
 
 
 /**
@@ -82,10 +80,9 @@ namespace app {
 
     /**
      * @brief           Read input and return as an integer.
-     * @param[in]       platform   Reference to the hal platform object.
      * @return          Integer value corresponding to the user input.
      **/
-    int ReadUserInputAsInt(hal_platform& platform);
+    int ReadUserInputAsInt();
 
 #if VERIFY_TEST_OUTPUT
     /**
diff --git a/source/hal/CMakeLists.txt b/source/hal/CMakeLists.txt
index 10016c2..37bf267 100644
--- a/source/hal/CMakeLists.txt
+++ b/source/hal/CMakeLists.txt
@@ -39,8 +39,6 @@ target_include_directories(${HAL_TARGET}
 target_sources(${HAL_TARGET}
     PRIVATE
     source/hal.c
-    source/data_psn.c
-    source/data_acq.c
     source/hal_timer.c)
 
 if (DEFINED VERIFY_TEST_OUTPUT)
diff --git a/source/hal/include/data_acq.h b/source/hal/include/data_acq.h
deleted file mode 100644
index 965fbe5..0000000
--- a/source/hal/include/data_acq.h
+++ /dev/null
@@ -1,52 +0,0 @@
-/*
- * Copyright (c) 2021 Arm Limited. All rights reserved.
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#ifndef DATA_ACQ_H
-#define DATA_ACQ_H
-
-/**
- * This file is the top level abstraction for the data acquisition module.
- **/
-#include <stdint.h>
-
-/* Structure to encompass the data acquisition module and it's methods. */
-typedef struct data_acquisition_module {
-    int inited;                 /**< initialised or not. */
-    char system_name[8];        /**< name(s) of the channel in use. */
-    int (* system_init)(void);  /**< channel initialisation function. */
-
-    /* Function to go and check if there are any events that require handling. */
-    int (* get_input)(char *user_input, int size);
-} data_acq_module;
-
-/**
- * @brief           Initialise the data acquisition channel: goes and
- *                  sets the required channel up for usage.
- * @param[in,out]   module  Pointer to a pre-allocated data
- *                          acquisition structure object.
- * @return          0 if successful, error code otherwise.
- **/
-int data_acq_channel_init(data_acq_module *module);
-
-/**
- * @brief           Releases the data acquisition channel.
- * @param[in,out]   module  Pointer to a pre-allocated data
- *                          acquisition structure object.
- * @return          0 if successful, error code otherwise.
- **/
-int data_acq_channel_release(data_acq_module *module);
-
-#endif /* DATA_ACQ_H */
diff --git a/source/hal/include/data_psn.h b/source/hal/include/data_psn.h
deleted file mode 100644
index 05d7649..0000000
--- a/source/hal/include/data_psn.h
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
- * Copyright (c) 2021-2022 Arm Limited. All rights reserved.
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#ifndef DATA_PSN_H
-#define DATA_PSN_H
-
-/**
- * This file is the top level abstraction for the data presentation module
- **/
-#include <stdint.h>
-#include <stddef.h>
-#include <stdbool.h>
-
-/* Structure to encompass the data presentation module and it's methods */
-typedef struct data_presentation_module {
-    int inited;                 /**< initialised or not */
-    char system_name[8];        /**< name of the system in use */
-    int (* system_init)(void);  /**< pointer to init function */
-
-    /** Pointer to the image presentation function */
-    int (* present_data_image)(const uint8_t *data, const uint32_t width,
-        const uint32_t height, const uint32_t channels,
-        const uint32_t pos_x, const uint32_t pos_y,
-        const uint32_t downsample_factor);
-
-    /* Pointer to text presentation function */
-    int (* present_data_text)(const char *str, const size_t str_sz,
-        const uint32_t pos_x, const uint32_t pos_y,
-        const bool allow_multiple_lines);
-
-    /* Pointer to box presentation function */
-    int (* present_box)(const uint32_t pos_x, const uint32_t pos_y,
-        const uint32_t width, const uint32_t height, const uint16_t color);
-
-    /* Pointer to clear presentation function */
-    int (* clear)(const uint16_t color);
-
-    /* Pointer to set text color presentation function */
-    int (* set_text_color)(const uint16_t color);
-} data_psn_module;
-
-
-/**
- * @brief           Initialises the data presentation system.
- * @param[in,out]   module  Pointer to a pre-allocated data
- *                          presentation structure object.
- * @return          0 if successful, error code otherwise.
- **/
-int data_psn_system_init(data_psn_module *module);
-
-/**
- * @brief           Releases the data presentation system.
- * @param[in,out]   module  Pointer to a pre-allocated data
- *                          presentation structure object.
- * @return          0 if successful, error code otherwise.
- **/
-int data_psn_system_release(data_psn_module *module);
-
-#endif /* DATA_PSN_H */
diff --git a/source/hal/include/hal.h b/source/hal/include/hal.h
index 6335e6d..25ea1e2 100644
--- a/source/hal/include/hal.h
+++ b/source/hal/include/hal.h
@@ -28,20 +28,18 @@
 extern "C" {
 #endif
 
-#include "platform_drivers.h"           /* Platform drivers */
-#include "data_acq.h"                   /* Data acquisition abstraction */
-#include "data_psn.h"                   /* Data presentation abstraction */
-#include "timer.h"                      /* Timer/profiler API */
+#include "platform_drivers.h"   /* Platform drivers */
+#include "timer.h"              /* Timer/profiler API */
+#include "hal_lcd.h"            /* LCD functions */
 
 #include <inttypes.h>
+#include <stdbool.h>
 
 /* Structure to define a platform context to be used by the application */
 typedef struct hal_platform_context {
     int inited;                         /**< initialised */
     char plat_name[64];                 /**< name of this platform */
-    data_acq_module * data_acq;         /**< data acquisition module pointer */
-    data_psn_module * data_psn;         /**< data presentation module pointer */
-    platform_timer *  timer;            /**< timer */
+    platform_timer* timer;              /**< timer */
     int (* platform_init)();            /**< pointer to platform initialisation function */
     void (* platform_release)();        /**< pointer to platform release function */
 } hal_platform;
@@ -50,13 +48,10 @@ typedef struct hal_platform_context {
  * @brief           Initialise the HAL structure based on compile time config. This
  *                  should be called before any other function in this API.
  * @param[in,out]   platform    Pointer to a pre-allocated platform struct.
- * @param[in,out]   data_acq    Pointer to a pre-allocated data acquisition module.
- * @param[in,out]   data_psn    Pointer to a pre-allocated data presentation module.
  * @param[in,out]   timer       Pointer to a pre-allocated timer module.
  * @return          0 if successful, error code otherwise.
  **/
-int hal_init(hal_platform *platform, data_acq_module *data_acq,
-    data_psn_module *data_psn, platform_timer *timer);
+int hal_init(hal_platform* platform, platform_timer* timer);
 
 
 /**
@@ -66,7 +61,7 @@ int hal_init(hal_platform *platform, data_acq_module *data_acq,
  *                          platform structure.
  * @return      0 if successful, error code otherwise.
  **/
-int hal_platform_init(hal_platform *platform);
+int hal_platform_init(hal_platform* platform);
 
 
 /**
@@ -74,7 +69,15 @@ int hal_platform_init(hal_platform *platform);
  * @param[in]   platform    pointer to a pre-allocated and initialised
  *                          platform structure.
  **/
-void hal_platform_release(hal_platform *platform);
+void hal_platform_release(hal_platform* platform);
+
+/**
+ * @brief       Gets user input from the stdin interface.
+ * @param[out]  user_input  Pointer to a buffer where the input will be stored.
+ * @param[in]   size        Buffer size in bytes.
+ * @return      True if successful, false otherwise.
+ */
+bool hal_get_user_input(char* user_input, int size);
 
 #ifdef __cplusplus
 }
diff --git a/source/hal/include/hal_lcd.h b/source/hal/include/hal_lcd.h
new file mode 100644
index 0000000..0a484c5
--- /dev/null
+++ b/source/hal/include/hal_lcd.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2021-2022 Arm Limited. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef HAL_LCD_H
+#define HAL_LCD_H
+/**
+ * This file is the top level abstraction for the LCD related functions
+ **/
+
+#include "lcd_img.h"
+
+#include <stdint.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+/**
+ * See lcd_img.h for function docstrings.
+ * In the following macro definitions:
+ * d = data (pointer)
+ * w = width
+ * h = height
+ * c = channels
+ * x = x position
+ * y = y position
+ * s = down-sample factor (images)
+ * m = allow multiple lines (text)
+ * cl = colour
+ */
+#define hal_lcd_init()                          lcd_init()
+#define hal_lcd_display_image(d,w,h,c,x,y,s)    lcd_display_image(d,w,h,c,x,y,s)
+#define hal_lcd_display_text(s,l,x,y,m)         lcd_display_text(s,l,x,y,m)
+#define hal_lcd_display_box(x,y,w,h,cl)         lcd_display_box(x,y,w,h,cl)
+#define hal_lcd_clear(cl)                       lcd_clear(cl)
+#define hal_lcd_set_text_color(cl)              lcd_set_text_color(cl)
+
+#endif /* HAL_LCD_H */
diff --git a/source/hal/source/data_acq.c b/source/hal/source/data_acq.c
deleted file mode 100644
index ec6c725..0000000
--- a/source/hal/source/data_acq.c
+++ /dev/null
@@ -1,61 +0,0 @@
-/*
- * Copyright (c) 2022 Arm Limited. All rights reserved.
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include "data_acq.h"
-
-#include "log_macros.h"
-#include "platform_drivers.h"
-
-#include <assert.h>
-#include <stdlib.h>
-#include <string.h>
-
-/**
- * @brief       Get the user input from USART.
- * @param[out]  user_input  String read from the UART block.
- * @param[in]   size        String read length.
- * @return      0 if successful, error code otherwise.
- **/
-static int get_uart_user_input(char* user_input, int size)
-{
-    if (1 != GetLine(user_input, size - 1)) {
-        return 1;
-    }
-    return 0;
-}
-
-int data_acq_channel_init(data_acq_module* module)
-{
-    assert(module);
-
-    /* UART should have been initialised with low level initialisation
-     * routines. */
-    module->system_init = NULL;
-
-    strncpy(module->system_name, "UART", sizeof(module->system_name));
-    module->get_input = get_uart_user_input;
-    module->inited = 1;
-
-    return !(module->inited);
-}
-
-int data_acq_channel_release(data_acq_module* module)
-{
-    assert(module);
-    module->inited = 0;
-    module->get_input = NULL;
-    return 0;
-}
diff --git a/source/hal/source/data_psn.c b/source/hal/source/data_psn.c
deleted file mode 100644
index de088d7..0000000
--- a/source/hal/source/data_psn.c
+++ /dev/null
@@ -1,46 +0,0 @@
-/*
- * Copyright (c) 2022 Arm Limited. All rights reserved.
- * SPDX-License-Identifier: Apache-2.0
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-#include "data_psn.h"
-
-#include "lcd_img.h"
-#include "platform_drivers.h"
-
-#include <assert.h>
-#include <string.h>
-
-int data_psn_system_init(data_psn_module* module)
-{
-    assert(module);
-
-    /* LCD output supported. */
-    module->system_init = lcd_init;
-    module->present_data_image = lcd_display_image;
-    module->present_data_text = lcd_display_text;
-    module->present_box = lcd_display_box;
-    module->set_text_color = lcd_set_text_color;
-    module->clear = lcd_clear;
-    strncpy(module->system_name, "lcd", sizeof(module->system_name));
-    module->inited =  !module->system_init();
-    return !module->inited;
-}
-
-int data_psn_system_release(data_psn_module* module)
-{
-    assert(module);
-    module->inited = 0;
-    return 0;
-}
diff --git a/source/hal/source/hal.c b/source/hal/source/hal.c
index 2715a17..d6028e7 100644
--- a/source/hal/source/hal.c
+++ b/source/hal/source/hal.c
@@ -23,13 +23,8 @@
 #include <assert.h>
 #include <string.h>
 
-int hal_init(hal_platform* platform, data_acq_module* data_acq,
-    data_psn_module* data_psn, platform_timer* timer)
+int hal_init(hal_platform* platform, platform_timer* timer)
 {
-    assert(platform && data_acq && data_psn);
-
-    platform->data_acq  = data_acq;
-    platform->data_psn  = data_psn;
     platform->timer     = timer;
     platform->platform_init     = platform_init;
     platform->platform_release  = platform_release;
@@ -59,46 +54,33 @@ int hal_platform_init(hal_platform* platform)
         return state;
     }
 
-    /* Initialise the data acquisition module */
-    if (0 != (state = data_acq_channel_init(platform->data_acq))) {
-        if (!platform->data_acq->inited) {
-            printf_err("Failed to initialise data acq module: %s\n",
-                platform->data_acq->system_name);
-        }
-        hal_platform_release(platform);
+    /* Initialise LCD */
+    if (0 != (state = hal_lcd_init())) {
+        printf_err("hal_lcd_init failed\n");
         return state;
     }
 
-    /* Initialise the presentation module */
-    if (0 != (state = data_psn_system_init(platform->data_psn))) {
-        printf_err("Failed to initialise data psn module: %s\n",
-            platform->data_psn->system_name);
-        data_acq_channel_release(platform->data_acq);
-        hal_platform_release(platform);
-        return state;
-    }
-
-    /* Followed by the timer module */
+    /* Initialise the timer module */
     init_timer(platform->timer);
 
     info("%s platform initialised\n", platform->plat_name);
-    debug("Using %s module for data acquisition\n",
-            platform->data_acq->system_name);
-    debug("Using %s module for data presentation\n",
-        platform->data_psn->system_name);
-
     platform->inited = !state;
-
     return state;
 }
 
 void hal_platform_release(hal_platform *platform)
 {
     assert(platform && platform->platform_release);
-    data_acq_channel_release(platform->data_acq);
-    data_psn_system_release(platform->data_psn);
 
     hal_platform_clear(platform);
     info("Releasing platform %s\n", platform->plat_name);
     platform->platform_release();
 }
+
+bool hal_get_user_input(char* user_input, int size)
+{
+    if (1 != GetLine(user_input, size - 1)) {
+        return true;
+    }
+    return false;
+}
diff --git a/source/use_case/ad/src/MainLoop.cc b/source/use_case/ad/src/MainLoop.cc
index 5a289bf..e858320 100644
--- a/source/use_case/ad/src/MainLoop.cc
+++ b/source/use_case/ad/src/MainLoop.cc
@@ -78,7 +78,7 @@ void main_loop(hal_platform& platform)
         int menuOption = MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) {
             DisplayMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -93,7 +93,7 @@ void main_loop(hal_platform& platform)
                        NUMBER_OF_FILES-1);
                 fflush(stdout);
                 auto audioIndex = static_cast<uint32_t>(
-                        arm::app::ReadUserInputAsInt(platform));
+                        arm::app::ReadUserInputAsInt());
                 executionSuccessful = ClassifyVibrationHandler(caseContext,
                                                            audioIndex,
                                                            false);
diff --git a/source/use_case/ad/src/UseCaseHandler.cc b/source/use_case/ad/src/UseCaseHandler.cc
index 853ab08..5585f36 100644
--- a/source/use_case/ad/src/UseCaseHandler.cc
+++ b/source/use_case/ad/src/UseCaseHandler.cc
@@ -33,12 +33,11 @@ namespace app {
     /**
      * @brief           Presents inference results using the data presentation
      *                  object.
-     * @param[in]       platform    reference to the hal platform object
      * @param[in]       result      average sum of classification results
      * @param[in]       threshold   if larger than this value we have an anomaly
      * @return          true if successful, false otherwise
      **/
-    static bool PresentInferenceResult(hal_platform& platform, float result, float threshold);
+    static bool PresentInferenceResult(float result, float threshold);
 
     /**
      * @brief Returns a function to perform feature calculation and populates input tensor data with
@@ -64,7 +63,6 @@ namespace app {
     /* Vibration classification handler */
     bool ClassifyVibrationHandler(ApplicationContext& ctx, uint32_t clipIndex, bool runAll)
     {
-        auto& platform = ctx.Get<hal_platform&>("platform");
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
         constexpr uint32_t dataPsnTxtInfStartX = 20;
@@ -114,7 +112,7 @@ namespace app {
         auto audioDataStride = nMelSpecVectorsInAudioStride * frameStride;
 
         do {
-            platform.data_psn->clear(COLOR_BLACK);
+            hal_lcd_clear(COLOR_BLACK);
 
             auto currentIndex = ctx.Get<uint32_t>("clipIndex");
 
@@ -153,7 +151,7 @@ namespace app {
 
             /* Display message on the LCD - inference running. */
             std::string str_inf{"Running inference... "};
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                     str_inf.c_str(), str_inf.size(),
                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
             info("Running inference on audio clip %" PRIu32 " => %s\n", currentIndex, get_filename(currentIndex));
@@ -202,12 +200,12 @@ namespace app {
 
             /* Erase. */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                     str_inf.c_str(), str_inf.size(),
                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
             ctx.Set<float>("result", result);
-            if (!PresentInferenceResult(platform, result, scoreThreshold)) {
+            if (!PresentInferenceResult(result, scoreThreshold)) {
                 return false;
             }
 
@@ -221,13 +219,13 @@ namespace app {
     }
 
 
-    static bool PresentInferenceResult(hal_platform& platform, float result, float threshold)
+    static bool PresentInferenceResult(float result, float threshold)
     {
         constexpr uint32_t dataPsnTxtStartX1 = 20;
         constexpr uint32_t dataPsnTxtStartY1 = 30;
         constexpr uint32_t dataPsnTxtYIncr   = 16; /* Row index increment */
 
-        platform.data_psn->set_text_color(COLOR_GREEN);
+        hal_lcd_set_text_color(COLOR_GREEN);
 
         /* Display each result */
         uint32_t rowIdx1 = dataPsnTxtStartY1 + 2 * dataPsnTxtYIncr;
@@ -242,7 +240,7 @@ namespace app {
             anomalyResult += std::string("Everything fine, no anomaly detected!");
         }
 
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                 anomalyScore.c_str(), anomalyScore.size(),
                 dataPsnTxtStartX1, rowIdx1, false);
 
diff --git a/source/use_case/asr/src/MainLoop.cc b/source/use_case/asr/src/MainLoop.cc
index 40624f3..058211a 100644
--- a/source/use_case/asr/src/MainLoop.cc
+++ b/source/use_case/asr/src/MainLoop.cc
@@ -121,7 +121,7 @@ void main_loop(hal_platform& platform)
         int menuOption = MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) {
             DisplayMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -136,7 +136,7 @@ void main_loop(hal_platform& platform)
                        NUMBER_OF_FILES-1);
                 fflush(stdout);
                 auto clipIndex = static_cast<uint32_t>(
-                                    arm::app::ReadUserInputAsInt(platform));
+                                    arm::app::ReadUserInputAsInt());
                 executionSuccessful = ClassifyAudioHandler(caseContext,
                                                            clipIndex,
                                                            false);
diff --git a/source/use_case/asr/src/UseCaseHandler.cc b/source/use_case/asr/src/UseCaseHandler.cc
index 7bce2c6..420f725 100644
--- a/source/use_case/asr/src/UseCaseHandler.cc
+++ b/source/use_case/asr/src/UseCaseHandler.cc
@@ -36,13 +36,10 @@ namespace app {
     /**
      * @brief           Presents inference results using the data presentation
      *                  object.
-     * @param[in]       platform    Reference to the hal platform object.
      * @param[in]       results     Vector of classification results to be displayed.
      * @return          true if successful, false otherwise.
      **/
-    static bool PresentInferenceResult(
-                    hal_platform& platform,
-                    const std::vector<arm::app::asr::AsrResult>& results);
+    static bool PresentInferenceResult(const std::vector<arm::app::asr::AsrResult>& results);
 
     /* Audio inference classification handler. */
     bool ClassifyAudioHandler(ApplicationContext& ctx, uint32_t clipIndex, bool runAll)
@@ -50,8 +47,7 @@ namespace app {
         constexpr uint32_t dataPsnTxtInfStartX = 20;
         constexpr uint32_t dataPsnTxtInfStartY = 40;
 
-        auto& platform = ctx.Get<hal_platform&>("platform");
-        platform.data_psn->clear(COLOR_BLACK);
+        hal_lcd_clear(COLOR_BLACK);
 
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
@@ -103,7 +99,7 @@ namespace app {
 
         /* Loop to process audio clips. */
         do {
-            platform.data_psn->clear(COLOR_BLACK);
+            hal_lcd_clear(COLOR_BLACK);
 
             /* Get current audio clip index. */
             auto currentIndex = ctx.Get<uint32_t>("clipIndex");
@@ -136,7 +132,7 @@ namespace app {
 
             /* Display message on the LCD - inference running. */
             std::string str_inf{"Running inference... "};
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
@@ -192,13 +188,13 @@ namespace app {
 
             /* Erase. */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
             ctx.Set<std::vector<arm::app::asr::AsrResult>>("results", results);
 
-            if (!PresentInferenceResult(platform, results)) {
+            if (!PresentInferenceResult(results)) {
                 return false;
             }
 
@@ -212,14 +208,13 @@ namespace app {
     }
 
 
-    static bool PresentInferenceResult(hal_platform& platform,
-                                       const std::vector<arm::app::asr::AsrResult>& results)
+    static bool PresentInferenceResult(const std::vector<arm::app::asr::AsrResult>& results)
     {
         constexpr uint32_t dataPsnTxtStartX1 = 20;
         constexpr uint32_t dataPsnTxtStartY1 = 60;
         constexpr bool allow_multiple_lines = true;
 
-        platform.data_psn->set_text_color(COLOR_GREEN);
+        hal_lcd_set_text_color(COLOR_GREEN);
 
         info("Final results:\n");
         info("Total number of inferences: %zu\n", results.size());
@@ -243,7 +238,7 @@ namespace app {
         /* Get the decoded result for the combined result. */
         std::string finalResultStr = audio::asr::DecodeOutput(combinedResults);
 
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                             finalResultStr.c_str(), finalResultStr.size(),
                             dataPsnTxtStartX1, dataPsnTxtStartY1,
                             allow_multiple_lines);
diff --git a/source/use_case/img_class/src/MainLoop.cc b/source/use_case/img_class/src/MainLoop.cc
index 05322d1..7b67a19 100644
--- a/source/use_case/img_class/src/MainLoop.cc
+++ b/source/use_case/img_class/src/MainLoop.cc
@@ -60,7 +60,7 @@ void main_loop(hal_platform& platform)
         int menuOption = common::MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) {
             DisplayCommonMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -70,7 +70,7 @@ void main_loop(hal_platform& platform)
             case common::MENU_OPT_RUN_INF_CHOSEN: {
                 printf("    Enter the image index [0, %d]: ", NUMBER_OF_FILES-1);
                 fflush(stdout);
-                auto imgIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt(platform));
+                auto imgIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt());
                 executionSuccessful = ClassifyImageHandler(caseContext, imgIndex, false);
                 break;
             }
diff --git a/source/use_case/img_class/src/UseCaseHandler.cc b/source/use_case/img_class/src/UseCaseHandler.cc
index 1f1d78b..9061282 100644
--- a/source/use_case/img_class/src/UseCaseHandler.cc
+++ b/source/use_case/img_class/src/UseCaseHandler.cc
@@ -44,7 +44,6 @@ namespace app {
     /* Image inference classification handler. */
     bool ClassifyImageHandler(ApplicationContext& ctx, uint32_t imgIndex, bool runAll)
     {
-        auto& platform = ctx.Get<hal_platform&>("platform");
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
         constexpr uint32_t dataPsnImgDownscaleFactor = 2;
@@ -89,7 +88,7 @@ namespace app {
         std::vector<ClassificationResult> results;
 
         do {
-            platform.data_psn->clear(COLOR_BLACK);
+            hal_lcd_clear(COLOR_BLACK);
 
             /* Strings for presentation/logging. */
             std::string str_inf{"Running inference... "};
@@ -98,7 +97,7 @@ namespace app {
             LoadImageIntoTensor(ctx.Get<uint32_t>("imgIndex"), inputTensor);
 
             /* Display this image on the LCD. */
-            platform.data_psn->present_data_image(
+            hal_lcd_display_image(
                 static_cast<uint8_t *>(inputTensor->data.data),
                 nCols, nRows, nChannels,
                 dataPsnImgStartX, dataPsnImgStartY, dataPsnImgDownscaleFactor);
@@ -109,7 +108,7 @@ namespace app {
             }
 
             /* Display message on the LCD - inference running. */
-            platform.data_psn->present_data_text(str_inf.c_str(), str_inf.size(),
+            hal_lcd_display_text(str_inf.c_str(), str_inf.size(),
                                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
             /* Run inference over this image. */
@@ -122,7 +121,7 @@ namespace app {
 
             /* Erase. */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(str_inf.c_str(), str_inf.size(),
+            hal_lcd_display_text(str_inf.c_str(), str_inf.size(),
                                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
             auto& classifier = ctx.Get<ImgClassClassifier&>("classifier");
@@ -137,7 +136,7 @@ namespace app {
             arm::app::DumpTensor(outputTensor);
 #endif /* VERIFY_TEST_OUTPUT */
 
-            if (!PresentInferenceResult(platform, results)) {
+            if (!PresentInferenceResult(results)) {
                 return false;
             }
 
diff --git a/source/use_case/inference_runner/src/UseCaseHandler.cc b/source/use_case/inference_runner/src/UseCaseHandler.cc
index 1125830..2f4b7c8 100644
--- a/source/use_case/inference_runner/src/UseCaseHandler.cc
+++ b/source/use_case/inference_runner/src/UseCaseHandler.cc
@@ -116,7 +116,6 @@ static void DumpOutputs(const Model& model, const char* message)
 
 bool RunInferenceHandler(ApplicationContext& ctx)
 {
-    auto& platform = ctx.Get<hal_platform&>("platform");
     auto& profiler = ctx.Get<Profiler&>("profiler");
     auto& model = ctx.Get<Model&>("model");
 
@@ -143,9 +142,8 @@ bool RunInferenceHandler(ApplicationContext& ctx)
     std::string str_inf{"Running inference... "};
 
     /* Display message on the LCD - inference running. */
-    platform.data_psn->present_data_text(
-                            str_inf.c_str(), str_inf.size(),
-                            dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
+    hal_lcd_display_text(str_inf.c_str(), str_inf.size(),
+                         dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
     if (!RunInference(model, profiler)) {
         return false;
@@ -153,7 +151,7 @@ bool RunInferenceHandler(ApplicationContext& ctx)
 
     /* Erase. */
     str_inf = std::string(str_inf.size(), ' ');
-    platform.data_psn->present_data_text(
+    hal_lcd_display_text(
                             str_inf.c_str(), str_inf.size(),
                             dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
diff --git a/source/use_case/kws/src/MainLoop.cc b/source/use_case/kws/src/MainLoop.cc
index 044c957..76dff8c 100644
--- a/source/use_case/kws/src/MainLoop.cc
+++ b/source/use_case/kws/src/MainLoop.cc
@@ -87,7 +87,7 @@ void main_loop(hal_platform& platform)
         int menuOption = MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) {
             DisplayMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -97,7 +97,7 @@ void main_loop(hal_platform& platform)
             case MENU_OPT_RUN_INF_CHOSEN: {
                 printf("    Enter the audio clip index [0, %d]: ", NUMBER_OF_FILES-1);
                 fflush(stdout);
-                auto clipIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt(platform));
+                auto clipIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt());
                 executionSuccessful = ClassifyAudioHandler(caseContext, clipIndex, false);
                 break;
             }
diff --git a/source/use_case/kws/src/UseCaseHandler.cc b/source/use_case/kws/src/UseCaseHandler.cc
index 8dd7724..e04cefc 100644
--- a/source/use_case/kws/src/UseCaseHandler.cc
+++ b/source/use_case/kws/src/UseCaseHandler.cc
@@ -35,16 +35,14 @@ using KwsClassifier = arm::app::Classifier;
 namespace arm {
 namespace app {
 
-   
+
     /**
      * @brief           Presents inference results using the data presentation
      *                  object.
-     * @param[in]       platform    Reference to the hal platform object.
      * @param[in]       results     Vector of classification results to be displayed.
      * @return          true if successful, false otherwise.
      **/
-    static bool PresentInferenceResult(hal_platform& platform,
-                                       const std::vector<arm::app::kws::KwsResult>& results);
+    static bool PresentInferenceResult(const std::vector<arm::app::kws::KwsResult>& results);
 
     /**
      * @brief Returns a function to perform feature calculation and populates input tensor data with
@@ -68,7 +66,6 @@ namespace app {
     /* Audio inference handler. */
     bool ClassifyAudioHandler(ApplicationContext& ctx, uint32_t clipIndex, bool runAll)
     {
-        auto& platform = ctx.Get<hal_platform&>("platform");
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
         constexpr uint32_t dataPsnTxtInfStartX = 20;
@@ -137,7 +134,7 @@ namespace app {
         const float secondsPerSample = 1.0/audio::MicroNetKwsMFCC::ms_defaultSamplingFreq;
 
         do {
-            platform.data_psn->clear(COLOR_BLACK);
+            hal_lcd_clear(COLOR_BLACK);
 
             auto currentIndex = ctx.Get<uint32_t>("clipIndex");
 
@@ -171,7 +168,7 @@ namespace app {
 
             /* Display message on the LCD - inference running. */
             std::string str_inf{"Running inference... "};
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
             info("Running inference on audio clip %" PRIu32 " => %s\n", currentIndex,
@@ -223,13 +220,13 @@ namespace app {
 
             /* Erase. */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
             ctx.Set<std::vector<arm::app::kws::KwsResult>>("results", results);
 
-            if (!PresentInferenceResult(platform, results)) {
+            if (!PresentInferenceResult(results)) {
                 return false;
             }
 
@@ -242,61 +239,6 @@ namespace app {
         return true;
     }
 
-    static bool PresentInferenceResult(hal_platform& platform,
-                                       const std::vector<arm::app::kws::KwsResult>& results)
-    {
-        constexpr uint32_t dataPsnTxtStartX1 = 20;
-        constexpr uint32_t dataPsnTxtStartY1 = 30;
-        constexpr uint32_t dataPsnTxtYIncr   = 16;  /* Row index increment. */
-
-        platform.data_psn->set_text_color(COLOR_GREEN);
-        info("Final results:\n");
-        info("Total number of inferences: %zu\n", results.size());
-
-        /* Display each result */
-        uint32_t rowIdx1 = dataPsnTxtStartY1 + 2 * dataPsnTxtYIncr;
-
-        for (uint32_t i = 0; i < results.size(); ++i) {
-
-            std::string topKeyword{"<none>"};
-            float score = 0.f;
-            if (!results[i].m_resultVec.empty()) {
-                topKeyword = results[i].m_resultVec[0].m_label;
-                score = results[i].m_resultVec[0].m_normalisedVal;
-            }
-
-            std::string resultStr =
-                std::string{"@"} + std::to_string(results[i].m_timeStamp) +
-                std::string{"s: "} + topKeyword + std::string{" ("} +
-                std::to_string(static_cast<int>(score * 100)) + std::string{"%)"};
-
-            platform.data_psn->present_data_text(
-                                    resultStr.c_str(), resultStr.size(),
-                                    dataPsnTxtStartX1, rowIdx1, false);
-            rowIdx1 += dataPsnTxtYIncr;
-
-            if (results[i].m_resultVec.empty()) {
-                info("For timestamp: %f (inference #: %" PRIu32
-                     "); label: %s; threshold: %f\n",
-                     results[i].m_timeStamp, results[i].m_inferenceNumber,
-                     topKeyword.c_str(),
-                     results[i].m_threshold);
-            } else {
-                for (uint32_t j = 0; j < results[i].m_resultVec.size(); ++j) {
-                    info("For timestamp: %f (inference #: %" PRIu32
-                         "); label: %s, score: %f; threshold: %f\n",
-                         results[i].m_timeStamp,
-                         results[i].m_inferenceNumber,
-                         results[i].m_resultVec[j].m_label.c_str(),
-                         results[i].m_resultVec[j].m_normalisedVal,
-                         results[i].m_threshold);
-                }
-            }
-        }
-
-        return true;
-    }
-
     /**
      * @brief Generic feature calculator factory.
      *
@@ -344,6 +286,60 @@ namespace app {
         };
     }
 
+    static bool PresentInferenceResult(const std::vector<arm::app::kws::KwsResult>& results)
+    {
+        constexpr uint32_t dataPsnTxtStartX1 = 20;
+        constexpr uint32_t dataPsnTxtStartY1 = 30;
+        constexpr uint32_t dataPsnTxtYIncr   = 16;  /* Row index increment. */
+
+        hal_lcd_set_text_color(COLOR_GREEN);
+        info("Final results:\n");
+        info("Total number of inferences: %zu\n", results.size());
+
+        /* Display each result */
+        uint32_t rowIdx1 = dataPsnTxtStartY1 + 2 * dataPsnTxtYIncr;
+
+        for (uint32_t i = 0; i < results.size(); ++i) {
+
+            std::string topKeyword{"<none>"};
+            float score = 0.f;
+            if (!results[i].m_resultVec.empty()) {
+                topKeyword = results[i].m_resultVec[0].m_label;
+                score = results[i].m_resultVec[0].m_normalisedVal;
+            }
+
+            std::string resultStr =
+                    std::string{"@"} + std::to_string(results[i].m_timeStamp) +
+                    std::string{"s: "} + topKeyword + std::string{" ("} +
+                    std::to_string(static_cast<int>(score * 100)) + std::string{"%)"};
+
+            hal_lcd_display_text(
+                    resultStr.c_str(), resultStr.size(),
+                    dataPsnTxtStartX1, rowIdx1, false);
+            rowIdx1 += dataPsnTxtYIncr;
+
+            if (results[i].m_resultVec.empty()) {
+                info("For timestamp: %f (inference #: %" PRIu32
+                             "); label: %s; threshold: %f\n",
+                     results[i].m_timeStamp, results[i].m_inferenceNumber,
+                     topKeyword.c_str(),
+                     results[i].m_threshold);
+            } else {
+                for (uint32_t j = 0; j < results[i].m_resultVec.size(); ++j) {
+                    info("For timestamp: %f (inference #: %" PRIu32
+                                 "); label: %s, score: %f; threshold: %f\n",
+                         results[i].m_timeStamp,
+                         results[i].m_inferenceNumber,
+                         results[i].m_resultVec[j].m_label.c_str(),
+                         results[i].m_resultVec[j].m_normalisedVal,
+                         results[i].m_threshold);
+                }
+            }
+        }
+
+        return true;
+    }
+
     template std::function<void (std::vector<int16_t>&, size_t , bool, size_t)>
         FeatureCalc<int8_t>(TfLiteTensor* inputTensor,
                             size_t cacheSize,
diff --git a/source/use_case/kws_asr/src/MainLoop.cc b/source/use_case/kws_asr/src/MainLoop.cc
index a2beab3..096c966 100644
--- a/source/use_case/kws_asr/src/MainLoop.cc
+++ b/source/use_case/kws_asr/src/MainLoop.cc
@@ -156,7 +156,7 @@ void main_loop(hal_platform& platform)
         int menuOption = MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) {
             DisplayMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -171,7 +171,7 @@ void main_loop(hal_platform& platform)
                        NUMBER_OF_FILES-1);
                 fflush(stdout);
                 auto clipIndex = static_cast<uint32_t>(
-                        arm::app::ReadUserInputAsInt(platform));
+                        arm::app::ReadUserInputAsInt());
                 executionSuccessful = ClassifyAudioHandler(caseContext,
                                                            clipIndex,
                                                            false);
diff --git a/source/use_case/kws_asr/src/UseCaseHandler.cc b/source/use_case/kws_asr/src/UseCaseHandler.cc
index d598de6..1e1a400 100644
--- a/source/use_case/kws_asr/src/UseCaseHandler.cc
+++ b/source/use_case/kws_asr/src/UseCaseHandler.cc
@@ -53,11 +53,10 @@ namespace app {
     /**
      * @brief           Presents kws inference results using the data presentation
      *                  object.
-     * @param[in]       platform    reference to the hal platform object
      * @param[in]       results     vector of classification results to be displayed
      * @return          true if successful, false otherwise
      **/
-    static bool PresentInferenceResult(hal_platform& platform, std::vector<arm::app::kws::KwsResult>& results);
+    static bool PresentInferenceResult(std::vector<arm::app::kws::KwsResult>& results);
 
     /**
      * @brief           Presents asr inference results using the data presentation
@@ -66,7 +65,7 @@ namespace app {
      * @param[in]       results     vector of classification results to be displayed
      * @return          true if successful, false otherwise
      **/
-    static bool PresentInferenceResult(hal_platform& platform, std::vector<arm::app::asr::AsrResult>& results);
+    static bool PresentInferenceResult(std::vector<arm::app::asr::AsrResult>& results);
 
     /**
      * @brief Returns a function to perform feature calculation and populates input tensor data with
@@ -186,9 +185,8 @@ namespace app {
         std::vector<arm::app::kws::KwsResult> kwsResults;
 
         /* Display message on the LCD - inference running. */
-        auto& platform = ctx.Get<hal_platform&>("platform");
         std::string str_inf{"Running KWS inference... "};
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                             str_inf.c_str(), str_inf.size(),
                             dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
@@ -258,11 +256,11 @@ namespace app {
 
         /* Erase. */
         str_inf = std::string(str_inf.size(), ' ');
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                             str_inf.c_str(), str_inf.size(),
                             dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
-        if (!PresentInferenceResult(platform, kwsResults)) {
+        if (!PresentInferenceResult(kwsResults)) {
             return output;
         }
 
@@ -285,8 +283,7 @@ namespace app {
         constexpr uint32_t dataPsnTxtInfStartY = 40;
 
         auto& profiler = ctx.Get<Profiler&>("profiler");
-        auto& platform = ctx.Get<hal_platform&>("platform");
-        platform.data_psn->clear(COLOR_BLACK);
+        hal_lcd_clear(COLOR_BLACK);
 
         /* Get model reference. */
         auto& asrModel = ctx.Get<Model&>("asrmodel");
@@ -356,7 +353,7 @@ namespace app {
 
         /* Display message on the LCD - inference running. */
         std::string str_inf{"Running ASR inference... "};
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                 str_inf.c_str(), str_inf.size(),
                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
@@ -407,11 +404,11 @@ namespace app {
 
             /* Erase */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                         str_inf.c_str(), str_inf.size(),
                         dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
         }
-        if (!PresentInferenceResult(platform, asrResults)) {
+        if (!PresentInferenceResult(asrResults)) {
             return false;
         }
 
@@ -423,8 +420,7 @@ namespace app {
     /* Audio inference classification handler. */
     bool ClassifyAudioHandler(ApplicationContext& ctx, uint32_t clipIndex, bool runAll)
     {
-        auto& platform = ctx.Get<hal_platform&>("platform");
-        platform.data_psn->clear(COLOR_BLACK);
+        hal_lcd_clear(COLOR_BLACK);
 
         /* If the request has a valid size, set the audio index. */
         if (clipIndex < NUMBER_OF_FILES) {
@@ -457,14 +453,13 @@ namespace app {
     }
 
 
-    static bool PresentInferenceResult(hal_platform& platform,
-                                       std::vector<arm::app::kws::KwsResult>& results)
+    static bool PresentInferenceResult(std::vector<arm::app::kws::KwsResult>& results)
     {
         constexpr uint32_t dataPsnTxtStartX1 = 20;
         constexpr uint32_t dataPsnTxtStartY1 = 30;
         constexpr uint32_t dataPsnTxtYIncr   = 16;  /* Row index increment. */
 
-        platform.data_psn->set_text_color(COLOR_GREEN);
+        hal_lcd_set_text_color(COLOR_GREEN);
 
         /* Display each result. */
         uint32_t rowIdx1 = dataPsnTxtStartY1 + 2 * dataPsnTxtYIncr;
@@ -484,7 +479,7 @@ namespace app {
                     std::string{"s: "} + topKeyword + std::string{" ("} +
                     std::to_string(static_cast<int>(score * 100)) + std::string{"%)"};
 
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                         resultStr.c_str(), resultStr.size(),
                         dataPsnTxtStartX1, rowIdx1, 0);
             rowIdx1 += dataPsnTxtYIncr;
@@ -502,13 +497,13 @@ namespace app {
         return true;
     }
 
-    static bool PresentInferenceResult(hal_platform& platform, std::vector<arm::app::asr::AsrResult>& results)
+    static bool PresentInferenceResult(std::vector<arm::app::asr::AsrResult>& results)
     {
         constexpr uint32_t dataPsnTxtStartX1 = 20;
         constexpr uint32_t dataPsnTxtStartY1 = 80;
         constexpr bool allow_multiple_lines = true;
 
-        platform.data_psn->set_text_color(COLOR_GREEN);
+        hal_lcd_set_text_color(COLOR_GREEN);
 
         /* Results from multiple inferences should be combined before processing. */
         std::vector<arm::app::ClassificationResult> combinedResults;
@@ -528,7 +523,7 @@ namespace app {
 
         std::string finalResultStr = audio::asr::DecodeOutput(combinedResults);
 
-        platform.data_psn->present_data_text(
+        hal_lcd_display_text(
                     finalResultStr.c_str(), finalResultStr.size(),
                     dataPsnTxtStartX1, dataPsnTxtStartY1, allow_multiple_lines);
 
diff --git a/source/use_case/noise_reduction/src/MainLoop.cc b/source/use_case/noise_reduction/src/MainLoop.cc
index c6214e3..bcaff6d 100644
--- a/source/use_case/noise_reduction/src/MainLoop.cc
+++ b/source/use_case/noise_reduction/src/MainLoop.cc
@@ -98,7 +98,7 @@ void main_loop(hal_platform& platform)
 
         if (bUseMenu) {
             DisplayMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -108,7 +108,7 @@ void main_loop(hal_platform& platform)
             case MENU_OPT_RUN_INF_CHOSEN: {
                 printf("    Enter the audio clip IFM index [0, %d]: ", NUMBER_OF_FILES-1);
                 fflush(stdout);
-                auto clipIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt(platform));
+                auto clipIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt());
                 SetAppCtxClipIdx(caseContext, clipIndex);
                 executionSuccessful = NoiseReductionHandler(caseContext, false);
                 break;
diff --git a/source/use_case/noise_reduction/src/UseCaseHandler.cc b/source/use_case/noise_reduction/src/UseCaseHandler.cc
index 792b460..acb8ba7 100644
--- a/source/use_case/noise_reduction/src/UseCaseHandler.cc
+++ b/source/use_case/noise_reduction/src/UseCaseHandler.cc
@@ -64,8 +64,6 @@ namespace app {
             pMemDumpBytesWritten = ctx.Get<size_t*>("MEM_DUMP_BYTE_WRITTEN");
         }
         std::reference_wrapper<size_t> memDumpBytesWritten = std::ref(*pMemDumpBytesWritten);
-
-        auto& platform = ctx.Get<hal_platform&>("platform");
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
         /* Get model reference. */
@@ -106,7 +104,7 @@ namespace app {
             audioFileAccessorFunc = ctx.Get<std::function<const char*(const uint32_t)>>("featureFileNames");
         }
         do{
-            platform.data_psn->clear(COLOR_BLACK);
+            hal_lcd_clear(COLOR_BLACK);
 
             auto startDumpAddress = memDumpBaseAddr + memDumpBytesWritten;
             auto currentIndex = ctx.Get<uint32_t>("clipIndex");
@@ -158,7 +156,7 @@ namespace app {
                 std::string str_inf{"Running inference... "};
 
                 /* Display message on the LCD - inference running. */
-                platform.data_psn->present_data_text(
+                hal_lcd_display_text(
                             str_inf.c_str(), str_inf.size(),
                             dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
@@ -191,7 +189,7 @@ namespace app {
 
                 /* Erase. */
                 str_inf = std::string(str_inf.size(), ' ');
-                platform.data_psn->present_data_text(
+                hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
@@ -218,14 +216,14 @@ namespace app {
             IncrementAppCtxClipIdx(ctx);
 
             std::string clearString{' '};
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                     clearString.c_str(), clearString.size(),
                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
             std::string completeMsg{"Inference complete!"};
 
             /* Display message on the LCD - inference complete. */
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                     completeMsg.c_str(), completeMsg.size(),
                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
diff --git a/source/use_case/object_detection/src/MainLoop.cc b/source/use_case/object_detection/src/MainLoop.cc
index 4bec357..0f98c8a 100644
--- a/source/use_case/object_detection/src/MainLoop.cc
+++ b/source/use_case/object_detection/src/MainLoop.cc
@@ -67,7 +67,7 @@ void main_loop(hal_platform& platform)
         int menuOption = common::MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) {
             DisplayDetectionMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
         switch (menuOption) {
@@ -77,7 +77,7 @@ void main_loop(hal_platform& platform)
             case common::MENU_OPT_RUN_INF_CHOSEN: {
                 printf("    Enter the image index [0, %d]: ", NUMBER_OF_FILES-1);
                 fflush(stdout);
-                auto imgIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt(platform));
+                auto imgIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt());
                 executionSuccessful = ObjectDetectionHandler(caseContext, imgIndex, false);
                 break;
             }
diff --git a/source/use_case/object_detection/src/UseCaseHandler.cc b/source/use_case/object_detection/src/UseCaseHandler.cc
index 27d767d..f3b317e 100644
--- a/source/use_case/object_detection/src/UseCaseHandler.cc
+++ b/source/use_case/object_detection/src/UseCaseHandler.cc
@@ -30,31 +30,27 @@ namespace app {
     /**
      * @brief           Presents inference results along using the data presentation
      *                  object.
-     * @param[in]       platform           Reference to the hal platform object.
      * @param[in]       results            Vector of detection results to be displayed.
      * @return          true if successful, false otherwise.
      **/
-    static bool PresentInferenceResult(hal_platform& platform,
-                                       const std::vector<arm::app::object_detection::DetectionResult>& results);
+    static bool PresentInferenceResult(const std::vector<arm::app::object_detection::DetectionResult>& results);
 
     /**
      * @brief           Draw boxes directly on the LCD for all detected objects.
-     * @param[in]       platform           Reference to the hal platform object.
      * @param[in]       results            Vector of detection results to be displayed.
      * @param[in]       imageStartX        X coordinate where the image starts on the LCD.
      * @param[in]       imageStartY        Y coordinate where the image starts on the LCD.
      * @param[in]       imgDownscaleFactor How much image has been downscaled on LCD.
      **/
-    static void DrawDetectionBoxes(hal_platform& platform,
-                                   const std::vector<arm::app::object_detection::DetectionResult>& results,
-                                   uint32_t imgStartX,
-                                   uint32_t imgStartY,
-                                   uint32_t imgDownscaleFactor);
+    static void DrawDetectionBoxes(
+            const std::vector<arm::app::object_detection::DetectionResult>& results,
+           uint32_t imgStartX,
+           uint32_t imgStartY,
+           uint32_t imgDownscaleFactor);
 
     /* Object detection classification handler. */
     bool ObjectDetectionHandler(ApplicationContext& ctx, uint32_t imgIndex, bool runAll)
     {
-        auto& platform = ctx.Get<hal_platform&>("platform");
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
         constexpr uint32_t dataPsnImgDownscaleFactor = 1;
@@ -64,7 +60,7 @@ namespace app {
         constexpr uint32_t dataPsnTxtInfStartX = 150;
         constexpr uint32_t dataPsnTxtInfStartY = 40;
 
-        platform.data_psn->clear(COLOR_BLACK);
+        hal_lcd_clear(COLOR_BLACK);
 
         auto& model = ctx.Get<Model&>("model");
 
@@ -114,7 +110,7 @@ namespace app {
             image::RgbToGrayscale(curr_image, dstPtr, copySz);
 
             /* Display image on the LCD. */
-            platform.data_psn->present_data_image(
+            hal_lcd_display_image(
                 (channelsImageDisplayed == 3) ? curr_image : dstPtr,
                 nCols, nRows, channelsImageDisplayed,
                 dataPsnImgStartX, dataPsnImgStartY, dataPsnImgDownscaleFactor);
@@ -125,7 +121,7 @@ namespace app {
             }
 
             /* Display message on the LCD - inference running. */
-            platform.data_psn->present_data_text(str_inf.c_str(), str_inf.size(),
+            hal_lcd_display_text(str_inf.c_str(), str_inf.size(),
                                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
             /* Run inference over this image. */
@@ -138,7 +134,7 @@ namespace app {
 
             /* Erase. */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(str_inf.c_str(), str_inf.size(),
+            hal_lcd_display_text(str_inf.c_str(), str_inf.size(),
                                     dataPsnTxtInfStartX, dataPsnTxtInfStartY, false);
 
             /* Detector post-processing*/
@@ -153,14 +149,14 @@ namespace app {
                 results);
 
             /* Draw boxes. */
-            DrawDetectionBoxes(platform, results, dataPsnImgStartX, dataPsnImgStartY, dataPsnImgDownscaleFactor);
+            DrawDetectionBoxes(results, dataPsnImgStartX, dataPsnImgStartY, dataPsnImgDownscaleFactor);
 
 #if VERIFY_TEST_OUTPUT
             arm::app::DumpTensor(modelOutput0);
             arm::app::DumpTensor(modelOutput1);
 #endif /* VERIFY_TEST_OUTPUT */
 
-            if (!PresentInferenceResult(platform, results)) {
+            if (!PresentInferenceResult(results)) {
                 return false;
             }
 
@@ -173,11 +169,9 @@ namespace app {
         return true;
     }
 
-
-    static bool PresentInferenceResult(hal_platform& platform,
-                                       const std::vector<arm::app::object_detection::DetectionResult>& results)
+    static bool PresentInferenceResult(const std::vector<arm::app::object_detection::DetectionResult>& results)
     {
-        platform.data_psn->set_text_color(COLOR_GREEN);
+        hal_lcd_set_text_color(COLOR_GREEN);
 
         /* If profiling is enabled, and the time is valid. */
         info("Final results:\n");
@@ -192,8 +186,7 @@ namespace app {
         return true;
     }
 
-    static void DrawDetectionBoxes(hal_platform& platform,
-                                   const std::vector<arm::app::object_detection::DetectionResult>& results,
+    static void DrawDetectionBoxes(const std::vector<arm::app::object_detection::DetectionResult>& results,
                                    uint32_t imgStartX,
                                    uint32_t imgStartY,
                                    uint32_t imgDownscaleFactor)
@@ -202,20 +195,20 @@ namespace app {
 
         for (const auto& result: results) {
             /* Top line. */
-            platform.data_psn->present_box(imgStartX + result.m_x0/imgDownscaleFactor,
+            hal_lcd_display_box(imgStartX + result.m_x0/imgDownscaleFactor,
                     imgStartY + result.m_y0/imgDownscaleFactor,
                     result.m_w/imgDownscaleFactor, lineThickness, COLOR_GREEN);
             /* Bot line. */
-            platform.data_psn->present_box(imgStartX + result.m_x0/imgDownscaleFactor,
+            hal_lcd_display_box(imgStartX + result.m_x0/imgDownscaleFactor,
                     imgStartY + (result.m_y0 + result.m_h)/imgDownscaleFactor - lineThickness,
                     result.m_w/imgDownscaleFactor, lineThickness, COLOR_GREEN);
 
             /* Left line. */
-            platform.data_psn->present_box(imgStartX + result.m_x0/imgDownscaleFactor,
+            hal_lcd_display_box(imgStartX + result.m_x0/imgDownscaleFactor,
                     imgStartY + result.m_y0/imgDownscaleFactor,
                     lineThickness, result.m_h/imgDownscaleFactor, COLOR_GREEN);
             /* Right line. */
-            platform.data_psn->present_box(imgStartX + (result.m_x0 + result.m_w)/imgDownscaleFactor - lineThickness,
+            hal_lcd_display_box(imgStartX + (result.m_x0 + result.m_w)/imgDownscaleFactor - lineThickness,
                     imgStartY + result.m_y0/imgDownscaleFactor,
                     lineThickness, result.m_h/imgDownscaleFactor, COLOR_GREEN);
         }
diff --git a/source/use_case/vww/src/MainLoop.cc b/source/use_case/vww/src/MainLoop.cc
index 30e85bf..03d6196 100644
--- a/source/use_case/vww/src/MainLoop.cc
+++ b/source/use_case/vww/src/MainLoop.cc
@@ -58,7 +58,7 @@ void main_loop(hal_platform &platform)
         int menuOption = common::MENU_OPT_RUN_INF_NEXT;
         if (bUseMenu) { 
             DisplayCommonMenu();
-            menuOption = arm::app::ReadUserInputAsInt(platform);
+            menuOption = arm::app::ReadUserInputAsInt();
             printf("\n");
         }
 
@@ -69,7 +69,7 @@ void main_loop(hal_platform &platform)
             case common::MENU_OPT_RUN_INF_CHOSEN: {
                 printf("    Enter the image index [0, %d]: ", NUMBER_OF_FILES-1);
                 fflush(stdout);
-                auto imgIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt(platform));
+                auto imgIndex = static_cast<uint32_t>(arm::app::ReadUserInputAsInt());
                 executionSuccessful = ClassifyImageHandler(caseContext, imgIndex, false);
                 break;
             }
diff --git a/source/use_case/vww/src/UseCaseHandler.cc b/source/use_case/vww/src/UseCaseHandler.cc
index a47f191..56ba2b5 100644
--- a/source/use_case/vww/src/UseCaseHandler.cc
+++ b/source/use_case/vww/src/UseCaseHandler.cc
@@ -42,7 +42,6 @@ namespace app {
     /* Image inference classification handler. */
     bool ClassifyImageHandler(ApplicationContext &ctx, uint32_t imgIndex, bool runAll)
     {
-        auto& platform = ctx.Get<hal_platform &>("platform");
         auto& profiler = ctx.Get<Profiler&>("profiler");
 
         constexpr uint32_t dataPsnImgDownscaleFactor = 1;
@@ -89,7 +88,7 @@ namespace app {
         std::vector<ClassificationResult> results;
 
         do {
-            platform.data_psn->clear(COLOR_BLACK);
+            hal_lcd_clear(COLOR_BLACK);
 
             /* Strings for presentation/logging. */
             std::string str_inf{"Running inference... "};
@@ -98,7 +97,7 @@ namespace app {
             LoadImageIntoTensor(ctx.Get<uint32_t>("imgIndex"), inputTensor);
 
             /* Display this image on the LCD. */
-            platform.data_psn->present_data_image(
+            hal_lcd_display_image(
                 static_cast<uint8_t *>(inputTensor->data.data),
                 nCols, nRows, nChannels,
                 dataPsnImgStartX, dataPsnImgStartY, dataPsnImgDownscaleFactor);
@@ -115,7 +114,7 @@ namespace app {
             }
 
             /* Display message on the LCD - inference running. */
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
@@ -129,7 +128,7 @@ namespace app {
 
             /* Erase. */
             str_inf = std::string(str_inf.size(), ' ');
-            platform.data_psn->present_data_text(
+            hal_lcd_display_text(
                                 str_inf.c_str(), str_inf.size(),
                                 dataPsnTxtInfStartX, dataPsnTxtInfStartY, 0);
 
@@ -145,7 +144,7 @@ namespace app {
             arm::app::DumpTensor(outputTensor);
 #endif /* VERIFY_TEST_OUTPUT */
 
-            if (!PresentInferenceResult(platform, results)) {
+            if (!PresentInferenceResult(results)) {
                 return false;
             }