2 files changed, 78 insertions, 0 deletions
diff --git a/powerswitch2/Makefile b/powerswitch2/Makefile
new file mode 100644
index 0000000..104f084
--- /dev/null
+++ b/powerswitch2/Makefile
@@ -0,0 +1,39 @@
+DEVICE     = attiny2313
+CLOCK      = 8000000
+FUSES      = -U lfuse:w:0xe4:m -U hfuse:w:0xd9:m
+
+PROGRAMMER  =-c stk500v2
+PROGRAMMER +=-P /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_A800dAli-if00-port0
+# in ms should be at least 4 times less than clock speed
+SPEED      = 4 # for default 1Mhz clock
+#SPEED      = 0.34 # for 12Mhz clock
+DEFS    = -DF_CPU=$(CLOCK)UL
+LIBS    = -Wl,--relax,--gc-sections,--print-gc-sections,--entry=main
+LIBS = -Wl,--entry=main,--gc-sections,--rela
+CFLAGS  = -Wall -Werror -pedantic -std=c99
+CFLAGS += -Os -funsigned-bitfields -fpack-struct -fshort-enums
+CFLAGS += -mmcu=$(DEVICE) $(DEFS)
+#LDFLAGS = $(LIBS)
+
+all: main.hex size
+
+main.hex: main.c
+	avr-gcc -o main.elf $? $(CFLAGS) $(LDFLAGS)
+	avr-objcopy -j .text -j .data -O ihex main.elf main.hex
+
+f: flash
+flash: all
+	avrdude $(PROGRAMMER) -p $(DEVICE) -B $(SPEED) -U flash:w:main.hex:i
+
+fuse:
+	avrdude $(PROGRAMMER) -p $(DEVICE) -B $(SPEED) $(FUSES)
+
+clean:
+	rm -f *.o *.elf *.hex
+
+size:
+	avr-size --mcu=$(DEVICE) -t -A main.elf
+	avr-size --mcu=$(DEVICE) -C main.elf
+	avr-nm --size-sort main.elf
+
+
diff --git a/powerswitch2/main.c b/powerswitch2/main.c
new file mode 100644
index 0000000..63e5d5c
--- /dev/null
+++ b/powerswitch2/main.c
@@ -0,0 +1,39 @@
+#include <avr/io.h>
+#include <util/delay.h>
+
+static inline void uart_init();
+int main()
+{
+    /* serial */
+    uart_init();
+
+    /* data input */
+    PORTB &= ~0x0F;
+    DDRB  |=  0x0F;
+
+    for (;;)
+    {
+        while ((UCSRA & (1 << RXC)) == 0);
+        PORTB ^= UDR & 0x0F;
+
+        while ((UCSRA & (1 << UDRE)) == 0);
+        UDR = PORTB & 0x0F;
+    }
+
+    return 0;
+}
+
+static inline void uart_init()
+{
+    UCSRB |= (1 << RXEN)  | (1 << TXEN);
+    UCSRC |= (1 << UCSZ0) | (1 << UCSZ1);
+#define BAUD 38400
+#include <util/setbaud.h>
+    UBRRH = UBRRH_VALUE;
+    UBRRL = UBRRL_VALUE;
+#if USE_2X
+    UCSRA |= (1 << U2X);
+#else
+    UCSRA &= ~(1 << U2X);
+#endif
+}