first commitupstream/master

2 files changed, 96 insertions, 0 deletions

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 <msp430x20x2.h>  <-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 <io.h>
+#include <signal.h>
+
+
+#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
+}
+
+