Thanks to all, board is running well now, the solution was to change the pins 3 to 4, 4 to 5, 5 to 6 and 6 to 7. All is ok now. 73 de Augusto, OA4CVT I am using the EPIC software and a board without any mark, the LVP is clear in the dialog box but does not work. Maybe I have to use another programmer board. ----- Original Message ----- From: "Byron A Jeff" To: Sent: Tuesday, March 18, 2003 11:42 AM Subject: Re: How can I ser the RB6, RB7 and RB4 pins as general IO > On Tue, Mar 18, 2003 at 11:05:05AM -0500, Augusto Yipmantin - OA4CVT wrote: > > Hi Sid, > > > > Thank4s for your answer, what I have to do is to set 3 relays with the RB4, > > RB5 and RB6 and 3 leds with the RB1, RB2 and RB3, the RB3 does not turn to > > on, and checking the 877 data sheet just found in the special features > > section the configuration word must be changed to get general io pins in > > that port. > > That's partially true. RB3 is designated as the LVP pin. To get it back > to normal I/O simple program with a high voltage programmer and clear > the LVP bit. > > As for the others (and RB4 isn't included), the multiplexing is automatic > and modal. RB6 and RB7 are always general I/O when the PIC is running in > standard mode. Also they are always CLK and DATA respectively in programming > mode. So unless you are doing ICSP, there should be no conflicts. > > One last thing: The relays are probably not going to work being driven > directly from the I/O pin. Check the current requirement. Most likely it's > more than that max 25ma that the PIC I/O pin can drive. > > For a brief overview of relay drivers check out here: > > http://www.saburchill.com/tech/electronics/elect027.html > > BAJ > > > > Just with a little problem trying to set as Output Pins the RB6, RB7 and > > RB4 > > > > pins of an PIC16F877. > > > > By default RB4, RB6 and RB7 are multiplexed pins to Low Voltage Prog. > > > > Can any help me a little on how to change the Configuration Word to > > enable > > > > the general io feature in this pins ? > > > > > > > > Hello, OA4CVT > > > > > > I have used the pins on PortB on the 877 many times and I simply program > > them > > > as I want them to operate. B7 and B7 are ICSP pins but I just ignore > > that. > > > If youwant the pins as outputs, write trisb = 0. If you want them as > > inputs > > > write trisb = 255. If you use the pins for serout or serin, > > > theyautomatically fo to the proper state, then return to their preset > > state. > > -- > http://www.piclist.com hint: PICList Posts must start with ONE topic: > [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads > -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads