To answer Stefan's Questions: >I am using this programmer for 'in-circuit' programming. >After a while, I discovered this problems: > >What happens on the programmers outputs, if : >* The programmer is powered, but not connected to the PC >* The programmer is powered and connected to the PC, which is off >* The programmer is powered and connected to a running PC, but the > programmer Software is not started. These are the reasons why I am going to develop my own. Actually, I wanted to put the programmer in-circuit, just as you are. My design point is for the programmer to stand alone and power the prototype circuit (with a wall-wart - maybe you buy them at "Wal-Mart"? Sorry...) with a 7805 (To be able to source at least a couple of hundread mAs). Actually, my design requirements are: 1. Provide a socketed PIC for allowing pulling it in and out. With this, I wanted the clocking and reset on the card so I don't have to set it up anywhere else. 2. Use a ZIF Socket for the PIC (only 18 pin). This is a big point and the Augat ZIFs I was able to get have 0.040" wide pins which are too big for most protoboard sockets. Actually, right now I am using the ZIF plugged into an 18 pin DIP socket, plugged into a Protoboard. 3. Have the socketed PIC Signals available on a 0.100" header so it can be plugged into a protoboard easily. 4. Have the socketed PIC assembly provide power to the protoboard. This is why I want to plug in a Wall-Wart to provide power. 5. Allow the socketed PIC to run even if the Host PC isn't up and running. 6. Allow the PIC to be programmed In the development Circuit. 7. The programmer should communicate with the PC via a Serial Port, not a parallel port. 8. Provide RS-232 TX/RX for a cheap and easy way of providing a debug/communications port to the PIC. 9. Support/Program the C61/C71/C84 (all the 18 pin 14 bit PICs). >My programmer doesn't solves the last one... So, your three "problems" would be encompassed by my design. On most RS-232 DIY Programmers, TX is used as a clocking/data signal which is not acceptable for my design point of wanting to be able to communicate via RS-232. I didn't want to go with a parallel port programmer for two reasons. The first is, is basically cost - I don't want to get another parallel port for my PC. The second should be more obvious; by using an RS-232 Port, I have a cheap and easy way of providing a debug interface (I'm using HyperTerminal under Win/95 which doesn't cost anything and I don't have to write anything on the PC side). Up to now, I have been using LEDs to tell me what's going on. I'm sick of doing that and I thought a direct RS-232 Interface would be better with english (or at least my version of it) messages coming out of the program. I know I still have to write the PC/16C54 Programming/Control Software, but I don't see it as being a major hardship. >Are there recommended connector and pinout for in-circuit PIC >programming? The 16C54 will have interfaces to RB6, RB7, and _MCLR as well as be able to control power and the _MCLR Voltage. As far as I can tell, this is it. When the PIC is being programmed or it's power is off, I will assert the external reset line (to make sure nothing is driving the Socketted PIC - although this will be up to the circuit designer to make sure this is happening). myke > >St. > >-- > _____________________________________________________________ > | _____________ | > | Dipl.-Ing. Stefan M. Ranguelov /____________/| | > | ||||||||||||| | > | tel.: +49 (30) 20 181 251 | > | priv.: +49 (30) 513 66 23 | > | s-mail: D-10319 Berlin, Mellenseestr. 39/10 | > | --------------------------------------------------------- | > | e-mail: ranguelo@informatik.hu-berlin.de | > /) WWW: http://www.informatik.hu-berlin.de/~ranguelo (\ > / ) PGP key: on request or from WWW-page ( \ > _( (|_____________________________________________________________|) ) >/> > (((\ \) /,) / ) / >//))/ > (\\\\ \_/ / \ \_/ >///// > \ / \ / > \ _/ \_ / > > Today, the commercial sector is advancing computer and communication technology at a breakneck pace. In 1992, optical fiber was being installed within the continental U.S. at rates approaching the speed of sound (if computed as total miles of fiber divided by the number of seconds in the year). Aviation Week and Space Technology, October 28, 1996