Seven segment display handling and refactoring

Makefile

@@ -8,6 +8,7 @@ ROOT_DIR    := $(SRC_DIR)/root
 HAL_DIR     := $(SRC_DIR)/hal
 PROG_DIR    := $(SRC_DIR)/prog
 STATE_DIR   := $(SRC_DIR)/state
+SEG_DIR    := $(SRC_DIR)/seg
 
 INC_SRCH_PATH :=
 INC_SRCH_PATH += -I$(INCLUDE_DIR)
@@ -17,11 +18,12 @@ INC_SRCH_PATH += -I$(ROOT_DIR)
 INC_SRCH_PATH += -I$(HAL_DIR)
 INC_SRCH_PATH += -I$(PROG_DIR)
 INC_SRCH_PATH += -I$(STATE_DIR)
+INC_SRCH_PATH += -I$(SEG_DIR)
 
 LIB_SRCH_PATH := 
 LIB_SRCH_PATH += -L$(MAKE_DIR)/libs
 
-LIBS := -lhal -lprog -lstate -lc -lgcc
+LIBS := -lhal -lprog -lstate -lseg -lc -lgcc -lm
 
 # Toolchain
 CC  := arm-none-eabi-gcc
@@ -56,6 +58,7 @@ build: dep
 	@$(MAKE) -C $(HAL_DIR) -f hal.mk
 	@$(MAKE) -C $(PROG_DIR) -f prog.mk
 	@$(MAKE) -C $(STATE_DIR) -f state.mk
+	@$(MAKE) -C $(SEG_DIR) -f seg.mk
 	@$(MAKE) -C $(ROOT_DIR) -f root.mk
 
 full_clean: clean dep_clean
@@ -64,6 +67,7 @@ clean:
 	@$(MAKE) -C $(HAL_DIR) -f hal.mk clean
 	@$(MAKE) -C $(PROG_DIR) -f prog.mk clean
 	@$(MAKE) -C $(STATE_DIR) -f state.mk clean
+	@$(MAKE) -C $(SEG_DIR) -f seg.mk clean
 	@$(MAKE) -C $(ROOT_DIR) -f root.mk clean
 
 dep_clean:

src/prog/prog.c

@@ -31,44 +31,35 @@ const struct state DEFAULT_FSM[NUM_DEFAULT_STATES] = {
 	}
 };
 
-void write_builtin_led(uint8_t color, uint8_t mode)
-{
-	gpio_set_mode(PIN('C', color), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('C', color), mode);
-}
-
 void max_speed_action()
 {
-	gpio_set_mode(PIN('C', 14), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('C', 14), GPIO_OUTPUT_SET);
+	gpio_set_mode(LED_RED_PIN, GPIO_MODE_OUTPUT);
+	gpio_write(LED_RED_PIN, GPIO_OUTPUT_SET);
 }
 
 void max_speed_transition()
 {
-	gpio_set_mode(PIN('C', 14), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('C', 14), GPIO_OUTPUT_CLEAR);
+	gpio_write(LED_RED_PIN, GPIO_OUTPUT_CLEAR);
 }
 
 void trip_distance_action()
 {
-	gpio_set_mode(PIN('C', 15), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('C', 15), GPIO_OUTPUT_SET);
+	gpio_set_mode(LED_GREEN_PIN, GPIO_MODE_OUTPUT);
+	gpio_write(LED_GREEN_PIN, GPIO_OUTPUT_SET);
 }
 
 void trip_distance_transition()
 {
-	gpio_set_mode(PIN('C', 15), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('C', 15), GPIO_OUTPUT_CLEAR);
+	gpio_write(LED_GREEN_PIN, GPIO_OUTPUT_CLEAR);
 }
 
 void total_distance_action()
 {
-	gpio_set_mode(PIN('F', 0), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('F', 0), GPIO_OUTPUT_SET);
+	gpio_set_mode(LED_BLUE_PIN, GPIO_MODE_OUTPUT);
+	gpio_write(LED_BLUE_PIN, GPIO_OUTPUT_SET);
 }
 
 void total_distance_transition()
 {
-	gpio_set_mode(PIN('F', 0), GPIO_MODE_OUTPUT);
-	gpio_write(PIN('F', 0), GPIO_OUTPUT_CLEAR);
+	gpio_write(LED_BLUE_PIN, GPIO_OUTPUT_CLEAR);
 }

src/prog/prog.h

@@ -9,14 +9,18 @@
 #define PROG_H
 #include <stdint.h>
 
+#include "hal.h"
 #include "state.h"
 
 
-/* LED pin #'s. */
-enum {LED_COLOR_RED = 6, LED_COLOR_BLUE, LED_COLOR_ORANGE, LED_COLOR_GREEN};
-
-/* Write LED color on port to mode. */
-extern void write_builtin_led(uint8_t color, uint8_t mode);
+/* Pins */
+#define STATEBTN_PIN (PIN('C', 13))
+#define LED_RED_PIN (PIN('B', 5))
+#define LED_GREEN_PIN (PIN('B', 4))
+#define LED_BLUE_PIN (PIN('B', 3))
+#define SHIFT_SER_PIN (PIN('A', 10))
+#define SHIFT_RCLK_PIN (PIN('A', 9))
+#define SHIFT_SRCLK_PIN (PIN('A', 8))
 
 /* States for the default FSM. */
 enum {STATE_MAX_SPEED, STATE_TRIP_DISTANCE, STATE_TOTAL_DISTANCE, NUM_DEFAULT_STATES};

src/root/main.c

@@ -13,35 +13,58 @@
 #include "prog.h"
 #include "hal.h"
 #include "state.h"
+#include "seg.h"
 
 
 int main()
 {
 	uint32_t debounce_timer, debounce_period = 20;
 	uint32_t idle_timer, idle_period = 10000;
+	uint8_t is_idle = 0;
+	uint32_t seg_timer, seg_period = 1000;
 
-	uint16_t usrbtn = PIN('C', 13);
 	uint8_t button_pressed = 0;
-	gpio_set_mode(usrbtn, GPIO_MODE_INPUT);
+	gpio_set_mode(STATEBTN_PIN, GPIO_MODE_INPUT);
 
 	struct fsm machine;
 	fsm_init(&machine, DEFAULT_FSM, STATE_MAX_SPEED);
-
+
+	gpio_set_mode(SHIFT_SER_PIN, GPIO_MODE_OUTPUT);
+	gpio_set_mode(SHIFT_RCLK_PIN, GPIO_MODE_OUTPUT);
+	gpio_set_mode(SHIFT_SRCLK_PIN, GPIO_MODE_OUTPUT);
+
+	seg_pins(SHIFT_SER_PIN, SHIFT_RCLK_PIN, SHIFT_SRCLK_PIN);
+	seg_clear_output();
+
 	NVIC_SetPriority (SysTick_IRQn, 0);
+	uint8_t x = 0;
 	for (;;) {
 		/* To prevent debounce, simply poll the button every 50ms or so. */
 		if (timer_expired(&debounce_timer, debounce_period, s_ticks)) {
-			if (!gpio_read(usrbtn) && !button_pressed) {  /* Button input is pull-up. */
+			if (!gpio_read(STATEBTN_PIN) && !button_pressed) {  /* Button input is pull-up. */
 				button_pressed = 1;
+				/* Capture first button press and re-do the action. */
+				if (is_idle) {
+					is_idle = 0;
+					fsm_action(&machine);
+					continue;
+				}
 
 				idle_timer = s_ticks + idle_period;
 				fsm_next(&machine);
-			} else if (gpio_read(usrbtn)) button_pressed = 0;
+			} else if (gpio_read(STATEBTN_PIN)) button_pressed = 0;
+		}
+		if (timer_expired(&idle_timer, idle_period, s_ticks) && !is_idle) {
+			is_idle = 1;
+			gpio_write(LED_RED_PIN, GPIO_OUTPUT_CLEAR);
+			gpio_write(LED_GREEN_PIN, GPIO_OUTPUT_CLEAR);
+			gpio_write(LED_BLUE_PIN, GPIO_OUTPUT_CLEAR);
+			seg_clear_output();
 		}
-		if (timer_expired(&idle_timer, idle_period, s_ticks)) {
-			gpio_write(PIN('C', 14), GPIO_OUTPUT_CLEAR);
-			gpio_write(PIN('C', 15), GPIO_OUTPUT_CLEAR);
-			gpio_write(PIN('F', 0), GPIO_OUTPUT_CLEAR);
+		if (timer_expired(&seg_timer, seg_period, s_ticks)) {
+			seg_clear_output();
+			seg_display_digit(x, 0);
+			++x; x = x % 10;
 		}
 	}
 

src/seg/seg.c

@@ -0,0 +1,110 @@
+/*
+ * filename:	seg.c
+ * date:	04.28.24
+ * author:	Lucas Merritt/merrittlj
+ * description:	Implementation for seg.h
+ */
+#include <stdint.h>
+#include <math.h>
+
+#include "seg.h"
+#include "hal.h"
+
+
+static uint16_t _display_num;
+static uint8_t _decimal_loc;
+static uint8_t _num_index;
+
+static uint16_t _ser;
+static uint16_t _rclk;
+static uint16_t _srclk;
+
+void seg_pins(uint16_t ser, uint16_t rclk, uint16_t srclk)
+{
+	_ser = ser;
+	_rclk = rclk;
+	_srclk = srclk;
+}
+
+void seg_update_output()
+{
+	gpio_write(_rclk, GPIO_OUTPUT_SET);
+	gpio_write(_rclk, GPIO_OUTPUT_CLEAR);
+}
+
+void seg_send_bit(uint8_t bit)
+{
+	gpio_write(_ser, bit);
+	gpio_write(_srclk, GPIO_OUTPUT_SET);
+	gpio_write(_srclk, GPIO_OUTPUT_CLEAR);
+	gpio_write(_ser, GPIO_OUTPUT_CLEAR);
+}
+
+void seg_clear_output()
+{
+	for (uint8_t i = 0; i < 8; ++i) seg_send_bit(0);
+	seg_update_output();
+}
+
+void seg_display_digit(uint8_t digit, uint8_t decimal_enabled)
+{
+	/*
+	 * Index correspondent to digit. Encodings are little-endian from A-G, with 0 = off and 1 = on.
+	 * Ex: 0 is all segments but G on, 0x3F = 0b0111111, we send 0, then 1, then 1, etc.
+	 */
+	uint8_t decode_nums[10] = {0x3F, 0x06, 0x5B, 0x4F, 0x66, 0x6D, 0x7D, 0x07, 0x7F, 0x6F};
+
+	/* We iterate in reverse order through the bits (ex: 0 = 0, then 1, then 1, etc.) because of how the shift register is buffered. */
+	seg_send_bit(decimal_enabled);
+	for (int8_t i = 6; i >= 0; --i) seg_send_bit((decode_nums[digit] >> i) & 1);
+
+	seg_update_output();
+}
+
+void seg_init(uint16_t num, uint8_t decimal)
+{
+	set_display_num(num);
+	set_decimal_loc(decimal);
+	set_num_index(0);
+}
+
+void set_display_num(uint16_t num)
+{
+	_display_num = num;
+}
+
+uint16_t get_display_num()
+{
+	return _display_num;
+}
+
+void set_decimal_loc(uint8_t decimal)
+{
+	_decimal_loc = decimal;
+}
+
+uint8_t get_decimal_loc()
+{
+	return _decimal_loc;
+}
+
+void set_num_index(uint8_t index)
+{
+	_num_index = index;
+}
+
+uint8_t get_num_index()
+{
+	return _num_index;
+}
+
+void seg_display_next()
+{
+	seg_clear_output();
+	/* TODO: set display to _num_index */
+	seg_display_digit((uint8_t)((_display_num / (uint16_t)(pow(10, 3 - _num_index))) % 10), _num_index == _decimal_loc);
+
+	++_num_index;
+	_num_index = _num_index % 4;
+}
+

src/seg/seg.h

@@ -0,0 +1,38 @@
+/*
+ * filename:	seg.h
+ * date:	04.28.24
+ * author:	Lucas Merritt/merrittlj
+ * description:	Driver code for 4-digit seven segment display with 8-bit shift register.
+ */
+
+#ifndef SEG_H
+#define SEG_H
+#include <stdint.h>
+
+#include "common.h"
+
+
+extern void seg_pins(uint16_t ser, uint16_t rclk, uint16_t srclk);  /* Set pins to use. */
+
+extern void seg_update_output();  /* Clock RCLK. */
+extern void seg_send_bit(uint8_t bit);  /* Send a bit to the shift register. */
+extern void seg_clear_output();
+extern void seg_display_digit(uint8_t digit, uint8_t decimal_enabled);
+
+extern void seg_init(uint16_t num, uint8_t decimal);
+
+/* To display a multiple-digit number, we have to multiplex. Set a number to display and display each digit with a function. */
+extern void set_display_num(uint16_t num);
+extern uint16_t get_display_num();
+
+/* Where the decimal is in _display_num, 0:3. */
+extern void set_decimal_loc(uint8_t decimal);
+extern uint8_t get_decimal_loc();
+
+/* Current digit index in _display_num, 0:3. */
+extern void set_num_index(uint8_t index);
+extern uint8_t get_num_index();
+
+extern void seg_display_next();  /* Display the next digit in the num. */
+
+#endif

src/seg/seg.mk

@@ -0,0 +1,19 @@
+LIB = $(MAKE_DIR)/libs/libseg.a
+SRCS = $(wildcard *.c)
+OBJS = $(patsubst %.c, %.o, $(SRCS))
+
+$(LIB): $(OBJS)
+	@mkdir -p $(MAKE_DIR)/libs
+	@$(AR) cr $@ $^
+	@echo "Archive $(notdir $@)"
+
+%.o: %.c
+	@$(CC) $(CFLAGS) -c $^ -o $@
+	@echo "CC $@"
+
+clean:
+	@$(RM) -f $(LIB) $(OBJS)
+	@$(RM) -f *.expand
+	@echo "Remove objects: $(OBJS)"
+
+.PHONY = clean

src/state/state.c

@@ -18,6 +18,11 @@ void fsm_init(struct fsm *f, const struct state *table, uint8_t state)
 	f->table[f->cur].action();
 }
 
+void fsm_action(struct fsm *f)
+{
+	f->table[f->cur].action();
+}
+
 void fsm_next(struct fsm *f)
 {
 	f->table[f->cur].transition();

src/state/state.h

@@ -30,6 +30,7 @@ struct fsm {
 
 /* Set appropriate variables in struct and start first state's action. */
 extern void fsm_init(struct fsm *f, const struct state *table, uint8_t state);
+extern void fsm_action(struct fsm *f);  /* Run current state action. */
 /* Transition out of current state, go to next state, start state action. */
 extern void fsm_next(struct fsm *f);