Can't turn on uart interrupt enable bit. What am I overlooking?

cuong nguyen1

Other Parts Discussed in Thread: MSP430WARE, MSP430FR5739

I turn on interrrupt enable in my code, but under Registers UCA0IE_UART, UCRXIE is 0. What am I doing wrong?

int main(void) {
WDTCTL = WDTPW | WDTHOLD; // Stop watchdog timer
init_clock();
init_uart0();
UCA0IE |= UCRXIE + UCTXCPTIE; //+ UCTXIE; // enable uart0 rx and tx
UCA1IE |= UCRXIE + UCTXCPTIE; //UART1 rx interrupt enable for compass
UCA0IE |= 0x09;
__bis_SR_register(GIE); //enable interrupts
while (1){}

//END OF CODE

PAUSED IN DEBUGGING

UCA0IE_UART

UCTXCPTIE 0
UCSTTIE 0
UCTXIE 0
UCRXIE 0

Same result for UCA1IE

over 12 years ago

0 MaciejKucia over 12 years ago

Mastermind 7925 points

Hi,

What chip?
Did you try Grace?
Did you see MSP430Ware examples?
Does UART work at all?
Do you clear flags in interrupt routine?

Regards,
Maciej

0 cuong nguyen1 over 12 years ago in reply to MaciejKucia

Intellectual 540 points

1. MSP430FR5739

2. Not familiar with Grace

3. I've work with interrupts before and have no problem when I am doing a single source code. Now I am doing multiple source code that interacts with one another.

4. Works when doing whole project in one source code.

5. Flags autoresets

0 MaciejKucia over 12 years ago in reply to cuong nguyen1

Mastermind 7925 points

Not sure what you mean by "multiple source code".

My recommendation is:

1. Create project with Grace. Build, program, go to debug. Check register values.

2. Debug your project and compare register settings.

Regards,
Maciej

0 Jens-Michael Gross over 12 years ago

Guru 227245 points

After power-on, UCSWRST bit is set,. While this bit is set, the UCxxIE bits are kept in reset state, you cannot alter them. YOu mus trelease the state machine by clearing UCSWRST bit before you can enable the interrupts.
Does init_uart0() do this? You shoudl post all the code, not jsut an excerpt. Very often, the problem is somewhere else and not where you think it would.

0 cuong nguyen1 over 12 years ago in reply to Jens-Michael Gross

Intellectual 540 points

That was it. Had to release it before enabling interrupt.

THANKS FOR ALL THE HELP!

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Can't turn on uart interrupt enable bit. What am I overlooking?