- Fixed drawing of round objects (Circles, Rounded Rects) using a lookup table

- Added function to read out the display_buffer via USB-Serial
 - Added basic structure and files for later complete firmware (still in progress)
 - Added Doc folder with schematic in it
 - Added Python script and batch file to read out the display buffer and open the image in gimp

Firmware/Core1_ADC.c

@@ -0,0 +1,115 @@
+/*
+ * ADC.c
+ *
+ * Created: Tue Sep 13 2022 19:51:36
+ *  Author Chris
+ */
+// ============================================================================================
+// Includes
+#include "Core1_ADC.h"
+
+#include "hardware/adc.h"
+#include "hardware/irq.h"
+#include "hardware/divider.h"
+
+
+// ============================================================================================
+// Defines
+#define YES							true
+#define NO							false
+
+#define ANALOG_REFERENCE_mV			3300ul
+#define ADC_INPUT_PIN				29
+
+
+// ============================================================================================
+// Variables
+static uint32_t _ADC_Result_Value;
+static uint32_t _ADC_Result_mV;
+
+const uint32_t	_ADC_Result_Num		= 11;
+const uint32_t	_ADC_Result_Denum	= 1;
+const bool		_ADC_Result_LowPass	= NO;
+
+
+// ============================================================================================
+// Function Declarations
+void Core1_ADC_Select_Next_MUX_Channel();
+void Core1_ADC_Set_Mux(uint channel);
+void Core1_ADC_Store_ADC_Result(uint16_t adc_value);
+uint32_t Core1_ADC_Low_Pass_Filter(int current_value, int new_value);
+
+
+/*******************************************************************
+	Interrupt Service Routines
+*******************************************************************/
+bool ISR_ADC()
+{
+	Core1_ADC_Store_ADC_Result(adc_fifo_get());
+}
+
+
+/*******************************************************************
+	Functions
+*******************************************************************/
+void Core1_ADC_Init()
+{
+	_ADC_Result_Value 	= 0;
+	_ADC_Result_mV 		= 0;
+	
+	adc_gpio_init(ADC_INPUT_PIN);
+	adc_init();
+	adc_select_input(3);
+	adc_fifo_setup(
+		true,  	// Write each completed conversion to the sample FIFO
+		false, 	// Enable DMA data request (DREQ)
+		1,	   	// DREQ (and IRQ) asserted when at least 1 sample present
+		false, 	// We won't see the ERR bit because of 8 bit reads; disable.
+		false	// Shift each sample to 8 bits when pushing to FIFO
+	);
+	adc_set_clkdiv(5999);		// One measurement every 0.125ms -> 8 measurements per 1 ms
+	adc_irq_set_enabled(true);
+
+	irq_set_exclusive_handler(ADC_IRQ_FIFO, (void *)ISR_ADC);
+	irq_set_enabled(ADC_IRQ_FIFO, true);
+
+	adc_run(true);
+}
+
+uint16_t Core1_ADC_Get_Result_Value(uint channel)
+{
+	return _ADC_Result_Value;
+}
+
+uint16_t Core1_ADC_Get_Result_mV(uint channel)
+{
+	return _ADC_Result_mV;
+}
+
+
+/*******************************************************************
+	Internal Functions
+*******************************************************************/
+void Core1_ADC_Store_ADC_Result(uint16_t adc_value)
+{
+	if(_ADC_Result_LowPass == YES) {
+		_ADC_Result_Value = (uint16_t)Core1_ADC_Low_Pass_Filter((float)_ADC_Result_Value, (float)adc_value);
+	} else {
+		_ADC_Result_Value = (uint32_t)adc_value;
+	}
+
+	_ADC_Result_mV	= ((_ADC_Result_Value * ANALOG_REFERENCE_mV * _ADC_Result_Num) / 4096) / _ADC_Result_Denum;
+}
+
+uint32_t Core1_ADC_Low_Pass_Filter(int current_value, int new_value)
+{
+	// Link: https://kiritchatterjee.wordpress.com/2014/11/10/a-simple-digital-low-pass-filter-in-c/
+	
+	const int Beta = 6;
+
+	current_value = (current_value << Beta) - current_value; 
+	current_value += new_value;
+	current_value >>= Beta;
+
+	return (uint32_t)current_value;
+}