initial

Makefile

@@ -0,0 +1,41 @@
+TOOLCHAIN_PREFIX=/opt/msp430-gcc
+CC=$(TOOLCHAIN_PREFIX)/bin/msp430-elf-gcc
+
+# regular
+MCU=msp430g2553
+COMMON=-Wall -mmcu=$(MCU) -std=gnu99 -I $(TOOLCHAIN_PREFIX)/include -Os -g0
+CFLAGS=$(COMMON)
+ASFLAGS=$(COMMON)
+
+LDFLAGS=-L $(TOOLCHAIN_PREFIX)/include -Wl,-Map,firmware.map -nostdlib -nostartfiles -T $(MCU).ld
+
+firmware.elf:	main.o
+	$(CC) -o $@ $(LDFLAGS) $^
+
+.c.o:	
+	$(CC) $(CFLAGS) -c $<
+
+.S.o:	
+	$(CC) $(ASFLAGS) -c $<
+
+
+.PHONY: all
+all:	firmware.elf
+
+.PHONY: clean
+clean:
+	-rm -f *.o *.elf *.map
+
+.PHONY: upload
+upload: firmware.elf
+	mspdebug rf2500 "prog firmware.elf"
+
+.PHONY: debug
+debug: upload
+	mspdebug rf2500 gdb &
+	ddd --debugger "msp430-gdb -x firmware.gdb"
+
+
+
+
+# /opt/msp430-gcc/bin/msp430-elf-gcc main.S -D_GNU_ASSEMBLER_ -Wall -Os -g -fdata-sections -ffunction-sections -mmcu=msp430g2553 -T /opt/msp430-gcc/include/msp430g2553.ld -I /opt/msp430-gcc/include/ -L /opt/msp430-gcc/include/ -nostdli

main.S

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+  .file "main.S"
+
+#include <msp430g2553.h>
+
+
+#define PC r0
+#define SP r1
+#define SR r2
+
+
+  ;; .text is the name of the section, it is a hint for the linker to
+  ;; allocate the section
+  ;; ax: a means allocatable by linker, x means executable
+  ;; @progbits is a hint for the linker to allocate this section into
+  ;; program memory (flash)
+  .section ".text","ax",@progbits
+
+_start:
+  ;; disable watchdog
+  mov.w   #WDTPW|WDTHOLD,&WDTCTL
+
+  ;; configure clock system to the highest frequency
+  mov.b   #DCO0|DCO1|DCO2,&DCOCTL
+  mov.b   #XT2OFF|RSEL0|RSEL1|RSEL2|RSEL3,&BCSCTL1
+  mov.b   #0,&BCSCTL2
+  mov.b   #0,&BCSCTL3
+
+  ;; initialize stack pointer with value from linker
+  mov.w   #__stack, SP
+
+init:
+  ;; configuration of GPIO Port1, use Bit6 as TA0.1
+  mov.b   #BIT6,&P1DIR
+  mov.b   #BIT6,&P1SEL
+
+  ;; timer configuration
+  ;;  configure and stop timer
+  ;;  cycle time is 56.25ns
+  mov.w   #ID_0|MC_0|TACLR|TASSEL_2,&TACTL
+  ;;  2.0us 
+  mov.w   #45,&TACCR0
+  ;;  a bit less
+  mov.w   #16,&TACCR1
+  ;;  configure output mode for TA0.1
+;  mov.w   #CCIE,&TACCTL0
+;  mov.w   #CCIE,&TACCTL1
+  mov.w   #OUTMOD_7,&TACCTL1
+  ;;  start timer in up mode
+  bis.w   #MC0,&TACTL
+
+  ;; enable interrupts
+  eint
+
+mainloop:
+  jmp     mainloop
+
+; --- timer isr ---
+;timer0_a0_isr:
+;  mov.b   #BIT0,&P1OUT
+;  reti
+
+;timer0_a1_isr:
+;  mov.b   #0,&P1OUT
+;  reti
+
+; --- interrupt vectors ---
+;  .section "__interrupt_vector_9","ax",@progbits
+;  .word   timer0_a1_isr
+;  .section "__interrupt_vector_10","ax",@progbits
+;  .word   timer0_a0_isr
+
+  ;; .resetvec comes from linker
+  .section ".resetvec","ax",@progbits
+  .word   _start
+
+  .end