From 30c9b4c926ec2dbcca923e75b1345ceb7f16498b Mon Sep 17 00:00:00 2001 From: szczys Date: Mon, 8 Nov 2010 13:10:19 -0600 Subject: first commit --- Makefile | 14 +++++++++++ main.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 96 insertions(+) create mode 100644 Makefile create mode 100644 main.c diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..1c1e2c5 --- /dev/null +++ b/Makefile @@ -0,0 +1,14 @@ +CC=msp430-gcc +CFLAGS=-Os -Wall -g -mmcu=msp430x2012 + +OBJS=main.o + + +all: $(OBJS) + $(CC) $(CFLAGS) -o main.elf $(OBJS) + +%.o: %.c + $(CC) $(CFLAGS) -c $< + +clean: + rm -fr main.elf $(OBJS) diff --git a/main.c b/main.c new file mode 100644 index 0000000..a52c4cf --- /dev/null +++ b/main.c @@ -0,0 +1,82 @@ +/* +Copyright (c) 2010 - Mike Szczys + + Permission is hereby granted, free of charge, to any person obtaining a copy + of this software and associated documentation files (the "Software"), to deal + in the Software without restriction, including without limitation the rights + to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + copies of the Software, and to permit persons to whom the Software is + furnished to do so, subject to the following conditions: + + The above copyright notice and this permission notice shall be included in + all copies or substantial portions of the Software. + + THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + THE SOFTWARE. +*/ + +//#include <-taken care of by including io.h and setting -mmcu=msp430x2012 in cflags + /* It's interesting to note that this is not the header + file for the chip we are using. This source code + is intended for the MSP430G2231 but there's no + header file for that specific ship. It apprears + That the MPS430x2012 is closely related and + I haven't observed any problems with using this + header file. */ +#include +#include + + +#define LED0 BIT0 +#define LED1 BIT6 +#define LED_DIR P1DIR +#define LED_OUT P1OUT + + +void initLEDs(void) { + LED_DIR |= LED0 + LED1; //Set LED pins as outputs + LED_OUT |= LED0 + LED1; //Turn on both LEDs +} + + +int main(void) { + + WDTCTL = WDTPW + WDTHOLD; // Stop WDT + /*Halt the watchdog timer + According to the datasheet the watchdog timer + starts automatically after powerup. It must be + configured or halted at the beginning of code + execution to avoid a system reset. Furthermore, + the watchdog timer register (WDTCTL) is + password protected, and requires the upper byte + during write operations to be 0x5A, which is the + value associated with WDTPW.*/ + + initLEDs(); //Setup LEDs + + BCSCTL3 |= LFXT1S_2; //Set ACLK to use internal VLO (12 kHz clock) + + TACTL = TASSEL__ACLK | MC__UP; //Set TimerA to use auxiliary clock in UP mode + TACCTL0 = CCIE; //Enable the interrupt for TACCR0 match + TACCR0 = 11999; /*Set TACCR0 which also starts the timer. At + 12 kHz, counting to 12000 should output + an LED change every 1 second. Try this + out and see how inaccurate the VLO can be */ + + WRITE_SR(GIE); //Enable global interrupts + + while(1) { + //Loop forever, interrupts take care of the rest + } +} + +interrupt(TIMERA0_VECTOR) TIMERA0_ISR(void) { + LED_OUT ^= (LED0 + LED1); //Toggle both LEDs +} + + -- cgit v1.2.3