Post by thread:Re: [PICLIST] [pic] pic16f84 rs232 10Mhz crystal

> Does anyone have any simple subroutines for transmitting serial rs232 data > from a P16F84 with a 10 MHz crystal.. I'm a newbie and I've been having > endless problems with the code I've been using, and was hoping someone might > have something better.. Did you check the most obvious place? (which is of course http://www.piclist.com) Wouter -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

sam woolf wrote: > > Does anyone have any simple subroutines for transmitting serial rs232 data > from a P16F84 with a 10 MHz crystal.. I'm a newbie and I've been having > endless problems with the code I've been using, and was hoping someone might > have something better.. > cheers, > .....samwKILLspam@spam@cogs.susx.ac.uk > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. This code is generated by ROMzap, it is at 19200 baud. Just pick your port and pins for Rx and Tx. At the moment they are set for RX = RC7 and TX = RC6. To use it you could try this... Loop call RxRoutine ; wait forever to receive a byte -> W reg call TxRoutine ; echo it back to sender goto Loop ; ; ; --------------- ; RECEIVE ROUTINE ; --------------- ; RxRoutine btfsc PORTC,7 ; wait for start bit goto InRxRoutine ; call HBDelay2 ; wait 1/2 bit length - 2 cycles movlw 9h movwf BCount ; RxLoop btfsc PORTC,7 ; start bit is lost during routine goto RxHiBit ; bcf STATUS,C ; receive start bit and 8 data bits goto RxLoBit ; RxHiBit bsf STATUS,C nop RxLoBit rrf RxHold,F call HBDelay4 ; wait 1/2 bit length - 4 cycles call HBDelay5 ; wait 1/2 bit length - 5 cycles decfsz BCount,F goto RxLoop ; movf RxHold,W return ; data returned in W Reg ; ; ---------------- ; TRANSMIT ROUTINE ; ---------------- ; TxRoutine movwf TxSend ; temp store data to be sent bcf PORTC,6 ; do start bit call HBDelay5 call HBDelay2 ; movlw 8h ; 8 data bits to send movwf BCount ; TxLoop rrf TxSend,F btfsc STATUS,C goto TxHiBit ; nop bcf PORTC,6 goto DoneBit ; TxHiBit bsf PORTC,6 goto $ + 1 ; DoneBit call HBDelay5 ; wait 1 bit length call HBDelay5 decfsz BCount,F goto TxLoop ; call DoRet nop bsf PORTC,6 ; stop bit call HBDelay1 call HBDelay DoRet return ; ; ----------------------------- ; HALF BIT DELAY FOR 19200 BAUD ; ----------------------------- ; HBDelay nop HBDelay1 nop HBDelay2 goto $ + 1 HBDelay4 nop HBDelay5 movlw 0x12 movwf BitWait BW decfsz BitWait,F goto BW CLRWDT return -- Best regards Tony mICros http://www.bubblesoftonline.com salesKILLspampicnpoke.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

Jal On Thu, 19 Apr 2001, sam woolf wrote: {Quote hidden}> Does anyone have any simple subroutines for transmitting serial rs232 data > from a P16F84 with a 10 MHz crystal.. I'm a newbie and I've been having > endless problems with the code I've been using, and was hoping someone might > have something better.. > cheers, > .....samwKILLspam.....cogs.susx.ac.uk > > -- > http://www.piclist.com hint: The PICList is archived three different > ways. See http://www.piclist.com/#archives for details. > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email EraseMElistservspam_OUTTakeThisOuTmitvma.mit.edu with SET PICList DIGEST in the body