Code Template

[RobG 1,892]

Here's a little code template I have created.

Not sure what I am going to use it for, but someone might find it helpful.

Handling of the interrupts is done in main rather than in interrupt routine itself.

 

#include "msp430g2231.h"

#define EV_TIMER BIT0
#define EV_PORT1 BIT1
#define EV_WDT BIT2
#define EV_USI BIT3

unsigned char events = 0;

void main(void)
{
WDTCTL = WDTPW + WDTHOLD;                 // stop WDT

// configure all here

__bis_SR_register(LPM0_bits + GIE); // switch to LPM0 with interrupts

while(1) {
	while(events) {
		if(events & EV_TIMER) {
			events &= EV_TIMER;
			// do your thing

			//clear TAIFG, etc.
			//enable interrupts, main, CCR0, CCR1, etc.
		} else  if(events & EV_PORT1) {
			events &= ~EV_PORT1;
			// do your thing

			//P1IFG &= ~BITn;	// clear IFG
			//P1IE |= BITn;		// enable interrupt
		} else  if(events & EV_WDT) {
			events &= ~EV_WDT;
			// do your thing

			IFG1 &= ~WDTIFG;
			//IE1 |= WDTIE;		// enable WDT interrupt
		} else  if(events & EV_USI) {
			events &= ~EV_USI;
			// do your thing

			USICTL1 &= ~USIIFG;
			//USICTL1 |= USIIE;	// enable interrupts
		}
	}
	__bis_SR_register(LPM0_bits); // switch to LPM0
}
}

// WDT interrupt service routine
#pragma vector=WDT_VECTOR
__interrupt void Watchdog_Timer (void)
{
//IE1 &= ~WDTIE;		// disable WDT interrupt
events |= EV_WDT;
__bic_SR_register_on_exit(LPM0_bits); // exit LPM0
} 

// Timer A interrupt service routine
#pragma vector=TIMERA0_VECTOR
__interrupt void Timer_A (void)
{
//disable interrupts, main, CCR0, CCR1, etc.
events |= EV_TIMER;
__bic_SR_register_on_exit(LPM0_bits); // exit LPM0
}

// Port 1 interrupt service routine
#pragma vector=PORT1_VECTOR
__interrupt void Port_1(void)
{ 
//P1IE &= ~BITn;			// disable interrupt
events |= EV_PORT1;
__bic_SR_register_on_exit(LPM0_bits); // exit LPM0
}

// USI interrupt service routine
#pragma vector = USI_VECTOR
__interrupt void USI_TXRX (void)
{
//USICTL1 &= ~USIIE;	// disable interrupts
events |= EV_USI;
__bic_SR_register_on_exit(LPM0_bits); // exit LPM0
}

// TODO Add ADC routine

[NatureTM 100]

Hey, that's interesting. I've been reading the uC/OS-III manual recently. This reminds me of how it deals with interrupts. It would be neat to implement priorities and communication between processes too. I guess you might now have much RAM or flash left over for your actual application if you did all that though.

[RobG 1,892]

When it comes to priority, all you need to do is reorder if-else blocks. For example, we are inside EV_PORT1, EV_WDT and EV_TIMER interrupts occur, our current block finishes, if-else block is executed again, EV_TIMER block is executed, and so on.

[GeekDoc 226]

I've been reading the uC/OS-III manual recently.

How is that book? I haven't cracked mine yet; haven't even looked at the terms of the "$1000" license we won.

[NatureTM 100]

I've been reading the uC/OS-III manual recently.

How is that book? I haven't cracked mine yet; haven't even looked at the terms of the "$1000" license we won.

 

Eh. Parts of it make me say, "that's really clever," or it shines some light on some other related topic about OS'es I was wondering about. The rest of the time it's like reading a technical document. Sometimes, the authors of books like this try to use some humor or analogies to make it an easier read. This guy didn't.

 

There were several times I wanted to skip using the OS altogether. There's a fair amount of extra coding involved with using it. Now that I've read a little more, I think it's worth it.

 

I've got some planning done on paper, and some parts arrived today, but I haven't actually written any code yet.

[GeekDoc 226]

I've got some planning done on paper, and some parts arrived today, but I haven't actually written any code yet.

You're way ahead of me. I just have the abstract I submitted. I don't think I'll get it done for the contest. :?