ADC integrated into console

digital-inputs/firmware/Makefile

@@ -131,6 +131,7 @@ CSRC = $(ALLCSRC) \
 CPPSRC = $(ALLCPPSRC) \
         main.cpp \
         source/usbconsole.cpp \
+        efilib.cpp \
         adc.cpp \
         digital_inputs.cpp \
 

digital-inputs/firmware/adc.cpp

@@ -9,7 +9,6 @@
  */
 
 
-#define ADC_GRP_NUM_CHANNELS   3
 #define ADC_GRP_BUF_DEPTH      8
 
 static adcsample_t samples[ADC_GRP_NUM_CHANNELS * ADC_GRP_BUF_DEPTH];
@@ -44,6 +43,20 @@ static const ADCConversionGroup adcgrpcfg = {
   /*.sqr3 = */0
 };
 
+static adcsample_t getAvgAdcValue(int index, adcsample_t *samples, int bufDepth, int numChannels) {
+	uint32_t result = 0;
+	for (int i = 0; i < bufDepth; i++) {
+		result += samples[index];
+		index += numChannels;
+	}
+
+	// this truncation is guaranteed to not be lossy - the average can't be larger than adcsample_t
+	return static_cast<adcsample_t>(result / bufDepth);
+}
+
+adcsample_t getAdcValue(int channel) {
+    return getAvgAdcValue(channel, samples, ADC_GRP_BUF_DEPTH, ADC_GRP_NUM_CHANNELS);
+}
 
 void initAnalogInputs() {
   /*

digital-inputs/firmware/adc.h

@@ -2,4 +2,9 @@
 
 #include "global.h"
 
-void initAnalogInputs();
+typedef uint16_t adcsample_t;
+
+#define ADC_GRP_NUM_CHANNELS   3
+
+void initAnalogInputs();
+adcsample_t getAdcValue(int channel);

digital-inputs/firmware/efilib.cpp

@@ -0,0 +1,63 @@
+
+#include <string.h>
+#include <stdint.h>
+#include "efilib.h"
+
+static char *ltoa_internal(char *p, uint32_t num, unsigned radix) {
+	constexpr int bufferLength = 10;
+
+	char buffer[bufferLength];
+
+	size_t idx = bufferLength - 1;
+
+	// First, we write from right-to-left so that we don't have to compute
+	// log(num)/log(radix)
+	do
+	{
+		auto digit = num % radix;
+
+		// Digits 0-9 -> '0'-'9'
+		// Digits 10-15 -> 'a'-'f'
+		char c = digit < 10
+			? digit + '0'
+			: digit + 'a' - 10;
+
+		// Write this digit in to the buffer
+		buffer[idx] = c;
+		idx--;
+	} while ((num /= radix) != 0);
+
+	idx++;
+
+	// Now, we copy characters in to place in the final buffer
+	while (idx < bufferLength)
+	{
+		*p++ = buffer[idx++];
+	}
+
+	return p;
+}
+
+/**
+ * @return pointer at the end zero symbol after the digits
+ */
+static char* itoa_signed(char *p, int num, unsigned radix) {
+	if (num < 0) {
+		*p++ = '-';
+		char *end = ltoa_internal(p, -num, radix);
+		*end = 0;
+		return end;
+	}
+	char *end = ltoa_internal(p, num, radix);
+	*end = 0;
+	return end;
+}
+
+/**
+ * Integer to string
+ *
+ * @return pointer at the end zero symbol after the digits
+ */
+char* itoa10(char *p, int num) {
+	return itoa_signed(p, num, 10);
+}

digital-inputs/firmware/efilib.h

@@ -8,3 +8,5 @@ constexpr size_t size(const T(&)[N]) {
     return N;
 }
 }
+
+char* itoa10(char *p, int num);

digital-inputs/firmware/main.cpp

@@ -20,6 +20,7 @@
 #include "chprintf.h"
 #include "digital_inputs.h"
 #include "adc.h"
+#include "efilib.h"
 
 BaseSequentialStream *chp = (BaseSequentialStream *)&EFI_CONSOLE_USB_DEVICE;
 
@@ -51,7 +52,16 @@ static THD_FUNCTION(Thread1, arg) {
 static THD_WORKING_AREA(consoleThread, 256);
 static void ConsoleThread(void*) {
     while (true) {
-            chprintf(chp, "Hello\r\n");
+        char buf[6];
+        for (int i = 0;i<ADC_GRP_NUM_CHANNELS;i++) {
+            int value = getAdcValue(i);
+            itoa10(buf, value);
+            chprintf(chp, buf);
+            chprintf(chp, " ");
+        }
+
+
+        chprintf(chp, "Hello\r\n");
         chThdSleepMilliseconds(200);
     }
 }