Post by thread:Sun based RS232 16C84 Programmer

David Tait wrote: > I must admit I'm talking to the wrong audience here on the PICLIST. Perhaps > there is no audience at all, but I thought there might be some hobbyist > somewhere in the world who doesn't own an IBM clone (has a Mac say), and who > doesn't mind chucking a few CMOS chips on a bit of stripboard to get a > PIC programmer for his/her trouble. > I haven't been folowing this thread too closely so forgive me if I misunderstand anyone. I've designed a PIC based programmer that interfaces to a serial port. I do most of my development on a Sun and I have a little controller program that will dump a .hex file to the programmer. I'm curious to know how many other pic hackers out there are interested in Sun based development. So far we have Ian King's assembler for linux/unix, and I have developed a simple programmer works via an RS232 interface. I'm currently working on a unix based simulator for the 16C84. If anyone wants to be a beta site, let me know. The interface for my programmer is pretty simple, the controller pic talks to the Sun at 9600 baud half duplex and support the following commands: H - MCLR High L - MCLR Low Pxxxx - Load program word xxxx to current location Cxxxx - Load config word xxxx to current location I - Increment address The PIC acks with an "A" if the operation succeeds and an "N" if it doesn't. Programming time for a 16C84 is ~20 seconds. The circuit looks pretty much like Dave mentioned earlier: MAX232=>PIC The target PIC's MCLR is driven with a transistor network from a regulated 13.2V supply, RB6 and RB8 are driven by the controller pic. I've layed out a board and have schematics. I can post these if anyone is interested. One caveat, I make my own boards with the iron on transparency method so I'm a big fan of surface mount components since I don't have to drill holes and my boards are usually more compact. If anyone is interested in these circuits I can post them, If you need a version that uses only DIP/through hole components, let me know and I'll see what I can do. -Steven

Hi Steven, > The interface for my programmer is pretty simple, the controller > pic talks to the Sun at 9600 baud half duplex ... Congratulations on getting your PIC programmer going. I guess if you look carefully at your software there is really very little that is Sun dependent. You have gone a long way in implementing "phase 2" of the machine independent universal PIC programmer project. But, and this goes to the heart of the problem I was trying to address, how did you program the PIC in your PIC programmer? David -- spam_OUTdavid.taitTakeThisOuTman.ac.uk P.S. I would be very interested in receiving more information on your project.

Steven T. Sprouse <.....Steven.SprouseKILLspam@spam@ENG.SUN.COM> wrote: >I haven't been folowing this thread too closely so forgive me if >I misunderstand anyone. > >I've designed a PIC based programmer that interfaces to a serial >port. > > .... > >The interface for my programmer is pretty simple, the controller >pic talks to the Sun at 9600 baud half duplex Steven: Yeah, you misunderstood (not that your comments aren't worthwhile, though)... The subject of the thread was David Tait's new programmer that doesn't require a "controller PIC". Solves the chicken-and-egg problem involved with getting that controller PIC programmed in the first place. I have a couple of PRO MATEs, so I don't need a DIY programmer, but personally, I think David's circuit is pretty cool. -Andy P.S. Motorola, of course, solved the chicken-and-egg problem with their 6805s long ago; each chip comes from the factory with bootstrap programming code in ROM... Build a simple programmer board (just a few chips, using PCB layout supplied by Mot), add a power supply, plug it into any computer's serial port, and away you go. -- Andrew Warren - fastfwdKILLspamix.netcom.com Fast Forward Engineering, Vista, California