PIC Basic PRO 16F877 USART Interrupt TX

[Darrel Taylor]

Oh Boy. Where to start. I guess from the beginning.

Since there isn't an OSC definition, I assume you're running at 4Mhz. And, with 4 Mhz, and BRGH (TXSTA.2) set to 0. The error rate for 9600 baud is 7%. That's really high. If you use HSER_TXSTA 24, which sets BRGH to 1, the error rate goes to 0.16%.

But then you manually set SPBRG to 25, which would be 2400 baud at 4mhz, so the 9600 gets discarded.

INTCON = %10010000 Along with turning Global interrups on, also enables the External Interrupt INT. But the rest of the program doesn't use INT.

'PIE1.5 = 1 ' enable interrupt on usart receive
This line is commented out, so the RX interrupt never gets enabled.

PIE1.4 = 1 ' enable interrupt on usart transmit
You cannot use Transmit interrupts with HSEROUT, they are not compatible.

Just like the compiler would do, I'll stop there and report [too many errors]

[BigH]

Hi Guys
Thanks, with your help I think I can now move in the right direction. I am beginning to think I should have stuck to Delphi and Window instead getting involved with these little Beast's . Thanks Again
Regards Henry

[mister_e]

i heard it often hurt the first time... good luck.

Don't be afraid, we all had and still have some problems with them sometimes. There's no problem... only learning opportunities