From bb15fdc634cbdb4b014096612c804c2980864699 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?King=20K=C3=A9vin?= <kingkevin@cuvoodoo.info>
Date: Wed, 24 Mar 2021 00:44:47 +0100
Subject: [PATCH] application: add channel initialisation

---
 application.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 49 insertions(+)

diff --git a/application.c b/application.c
index 174f0da..f896592 100644
--- a/application.c
+++ b/application.c
@@ -66,6 +66,12 @@ const uint8_t adc_channels[] = {ADC_CHANNEL17, ADC_CHANNEL(TARGET_CHANNEL), ADC_
 #define MUX_S2_PIN PB1 /**< pin to set S2 bit of analog multiplexer */
 #define MUX_S3_PIN PB2 /**< pin to set S3 bit of analog multiplexer */
 
+#define CHANNEL_NUMBERS 16 /**< number of target signals */
+static const uint32_t channel_ports[] = {GPIO_PORT(PB12), GPIO_PORT(PB13), GPIO_PORT(PB14), GPIO_PORT(PB15), GPIO_PORT(PA8), GPIO_PORT(PA9), GPIO_PORT(PA10), GPIO_PORT(PA15), GPIO_PORT(PB3), GPIO_PORT(PB4), GPIO_PORT(PB5), GPIO_PORT(PB6), GPIO_PORT(PB7), GPIO_PORT(PB8), GPIO_PORT(PB9), GPIO_PORT(PB10)}; /**< GPIO ports for signal pin */
+static const uint32_t channel_pins[] = {GPIO_PIN(PB12), GPIO_PIN(PB13), GPIO_PIN(PB14), GPIO_PIN(PB15), GPIO_PIN(PA8), GPIO_PIN(PA9), GPIO_PIN(PA10), GPIO_PIN(PA15), GPIO_PIN(PB3), GPIO_PIN(PB4), GPIO_PIN(PB5), GPIO_PIN(PB6), GPIO_PIN(PB7), GPIO_PIN(PB8), GPIO_PIN(PB9), GPIO_PIN(PB10)}; /**< GPIO pins for signal pin */
+static uint8_t channel_start = 0; /**< first signal of range to probe */
+static uint8_t channel_stop = CHANNEL_NUMBERS - 1; /**< last signal of range to probe */
+
 size_t putc(char c)
 {
 	size_t length = 0; // number of characters printed
@@ -82,6 +88,42 @@ size_t putc(char c)
 	return length; // return number of characters printed
 }
 
+/** get RCC from corresponding port
+ *  @param[in] port port address
+ *  @return RCC address corresponding to port
+ */
+static uint32_t port2rcc(uint32_t port)
+{
+	uint32_t rcc = 0;
+	switch (port) {
+	case GPIOA:
+		rcc = RCC_GPIOA;
+		break;
+	case GPIOB:
+		rcc = RCC_GPIOB;
+		break;
+	case GPIOC:
+		rcc = RCC_GPIOC;
+		break;
+	case GPIOD:
+		rcc = RCC_GPIOD;
+		break;
+	case GPIOE:
+		rcc = RCC_GPIOE;
+		break;
+	case GPIOF:
+		rcc = RCC_GPIOF;
+		break;
+	case GPIOG:
+		rcc = RCC_GPIOG;
+		break;
+	default: // unknown port
+		while (true); // halt firmware
+		break;
+	}
+	return rcc;
+}
+
 /** measure target and signal voltages
  *  @return voltages of channels
  */
@@ -557,6 +599,13 @@ void main(void)
 	mux_select(-1); // ensure it is disabled
 	puts("OK\n");
 
+	puts("setup signal pins: ");
+	for (uint8_t i = 0; i < CHANNEL_NUMBERS; i++) {
+		rcc_periph_clock_enable(port2rcc(channel_ports[i])); // enable clock for port domain
+		gpio_mode_setup(channel_ports[i], GPIO_MODE_INPUT, GPIO_PUPD_NONE, channel_pins[i]); // ensure pin is floating input
+	}
+	puts("OK\n");
+
 	puts("setup ADC to measure voltages: ");
 	rcc_periph_clock_enable(RCC_ADC1); // enable clock for ADC domain
 	adc_power_off(ADC1); // switch off ADC while configuring it