Post by thread:[PIC:]F876 USART problem

Hi All I am using 16f876 USART but I have encounter something odd below is a segment of my code banksel SPBRG ; bank0 movlw d'64' ; 19200 baud @ 20 Mhz Fosc +0.16 err movwf SPBRG movlw b'00100100' ; brgh = 1 movwf TXSTA ; enable Async Transmission, set brgh banksel RCSTA ; bank0 movlw b'10010000' movwf RCSTA ; enable Async Reception movf RCREG,w movf RCREG,w movf RCREG,w ; flush receive buffer Guess what i got a 5 voltage signal coming out of RC7/RX which is already configure as a input and all my recieve rountie did not work but the TX is still working anyone have encounter this before? Thanks -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.

What is connected to the RX pin? Do you have it connected to an RS-232 level shifter? If so, are you certain that the level shifter has the appropriate connections to ensure that the pin tied to RX gives the proper signal? Could the input to the Receive buffer on the level shifter be bad or floating? Mike H. {Quote hidden}>From: PSL <spam_OUTL030010TakeThisOuTSINGNET.COM.SG> >Reply-To: pic microcontroller discussion list <.....PICLISTKILLspam@spam@MITVMA.MIT.EDU> >To: PICLISTKILLspamMITVMA.MIT.EDU >Subject: [PIC:]F876 USART problem >Date: Fri, 9 Jan 2004 23:51:15 +0800 > >Hi All > > >I am using 16f876 USART but I have encounter something odd >below is a segment of my code > > > banksel SPBRG ; bank0 > movlw d'64' ; 19200 baud @ 20 Mhz Fosc +0.16 err > movwf SPBRG > movlw b'00100100' ; brgh = 1 > movwf TXSTA ; enable Async Transmission, set brgh > banksel RCSTA ; bank0 > movlw b'10010000' > movwf RCSTA ; enable Async Reception > movf RCREG,w > movf RCREG,w > movf RCREG,w ; flush receive buffer > >Guess what i got a 5 voltage signal coming out of RC7/RX which is already >configure as a input >and all my recieve rountie did not work but the TX is still working > >anyone have encounter this before? > >Thanks > >-- >http://www.piclist.com hint: The PICList is archived three different >ways. See http://www.piclist.com/#archives for details. _________________________________________________________________ Check your PC for viruses with the FREE McAfee online computer scan. http://clinic.mcafee.com/clinic/ibuy/campaign.asp?cid=3963 -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.