fw: Implement power management

firmware/Makefile

@@ -1,9 +1,10 @@
 MCU=atmega88
-CFLAGS=-g -Wall -Wno-multichar -Wno-overflow -mcall-prologues -mmcu=$(MCU) -O2 -DF_CPU=8000000 -IAVR-SSD1306/Files/
+gitrev=$(shell git describe --tags --dirty --always)
+CFLAGS=-g -Wall -Wno-multichar -Wno-overflow -mcall-prologues -mmcu=$(MCU) -O2 -DF_CPU=8000000 -DGITREV=\"$(gitrev)\" -IAVR-SSD1306/Files/
 LDFLAGS=-Wl,-gc-sections -Wl,-relax
 CC=avr-gcc
 TARGET=main
-OBJECT_FILES=main.o batmon.o input.o systick.o oled-display/font.o oled-display/i2c.o oled-display/lcd.o
+OBJECT_FILES=main.o pm.o batmon.o input.o systick.o oled-display/font.o oled-display/i2c.o oled-display/lcd.o
 
 all: $(TARGET).hex
 

firmware/main.c

@@ -6,6 +6,7 @@
 #include "input.h"
 #include "systick.h"
 #include "batmon.h"
+#include "pm.h"
 
 #define PORT_SPI(t) t##B
 #define PIN_SPI_CS (1 << 2)
@@ -66,28 +67,42 @@ uint8_t spi_proc()
 	return spi_cs;
 }
 
-void lcd_startup()
+void lcd_title(const char *msg1, const char *msg2)
 {
-	lcd_init(LCD_DISP_ON);
+	lcd_clrscr();
 	lcd_gotoxy(0, 0);
 	lcd_puts_p(PSTR("== Internet Radio =="));
 	lcd_drawLine(0, 9, 120, 9, WHITE);
 	lcd_gotoxy(0, 2);
-	lcd_puts_p(PSTR("Starting up."));
+	lcd_puts_p(msg1);
 	lcd_gotoxy(0, 3);
-	lcd_puts_p(PSTR("Please wait..."));
+	lcd_puts_p(msg2);
 	lcd_display();
 }
 
 int main()
 {
+	char *post_msg;
+
+	MCUSR &= ~(1 << WDRF);
+	WDTCSR = (1 << WDCE);
 	cli();
 
-	lcd_startup();
+	suspend();
+
+	lcd_init(LCD_DISP_ON);
+	lcd_title(PSTR("Starting IOC Rev."), PSTR(GITREV));
 	spi_init();
 	systick_init();
 	input_init();
 	batmon_init();
+	if (post_msg = post()) {
+		lcd_title(PSTR("POST Error!"), post_msg);
+		_delay_ms(2000);
+		reset();
+	}
+
+	lcd_title(PSTR("Starting up."), PSTR("Please wait..."));
 
 	_delay_ms(10);
 

firmware/oled-display/lcd.c

@@ -47,10 +47,7 @@
 #include "lcd.h"
 #include "font.h"
 #include <string.h>
-
-#if defined SPI
 #include <util/delay.h>
-#endif
 
 static struct {
     uint8_t x;
@@ -139,6 +136,11 @@ void lcd_data(uint8_t data[], uint16_t size) {
 #pragma mark -
 #pragma mark GENERAL FUNCTIONS
 void lcd_init(uint8_t dispAttr){
+    PORT_LCDP(DDR) |= PIN_LCDP;
+    PORT_LCDP(PORT) &= ~(PIN_LCDP);
+    _delay_ms(100);
+    PORT_LCDP(PORT) |= PIN_LCDP;
+    _delay_ms(100);
 #if defined I2C
     i2c_init();
 #elif defined SPI

firmware/oled-display/lcd.h

@@ -74,6 +74,8 @@ extern "C" {
     // e.g. 8 bit slave-adress:
     // 0x78 = adress 0x3C with cleared r/w-bit (write-mode)
 
+#define PORT_LCDP(t) t##C
+#define PIN_LCDP (1 << 3)
 
 #ifdef I2C
 #include "i2c.h"	// library for I2C-communication

firmware/pm.c

@@ -0,0 +1,64 @@
+#include <avr/io.h>
+#include <avr/sleep.h>
+#include <util/delay.h>
+#include <avr/interrupt.h>
+#include <avr/pgmspace.h>
+#include "pm.h"
+
+static void disable_periphery()
+{
+	cli();
+	WDTCSR = 0;
+	TWCR = 0;
+	SPCR = 0;
+	ADCSRA = 0;
+	DDRB = 0;
+	DDRC = 0;
+	DDRD = 0;
+	PORTB = 0;
+	PORTC = 0;
+	PORTD = (1 << 2); // Pullup for INT0
+}
+
+void suspend()
+{
+	disable_periphery();
+
+	EICRA = 0;
+	EIMSK = (1 << INT0);
+	SMCR = (1 << SM1) | (1 << SE);
+	sei();
+	sleep_cpu();
+	cli();
+
+	_delay_ms(50);
+	while (!(PIND & (1 << 2)));
+	_delay_ms(50);
+}
+
+ISR(INT0_vect)
+{
+	return;
+}
+
+void reset()
+{
+	disable_periphery();
+	// WDTCSR = (1 << WDE) | (1 << WDP2);
+	// For some reason, the WD reset locks up my chip,
+	// so let's just jump to the reset vector directly.
+	asm("ldi R16,0x00");
+	asm("push R16");
+	asm("push R16");
+	asm("push R16");
+	asm("push R16");
+	asm("ret");
+	while (1);
+}
+
+char* post()
+{
+	// TODO: Implement battery voltage check
+	_delay_ms(500);
+	return 0;
+}

firmware/pm.h

@@ -0,0 +1,7 @@
+#ifndef PM_H
+#define PM_H
+#include <avr/io.h>
+
+void suspend();
+
+#endif // PM_H