Buriedcode
Full Member level 6
diy usb pic programmer
Hi,
I've been desgining a dev board for PIC's (18-40 pins DIP's) and although its gonna have bootloading capability, I've been thinking about making a USB programmer for 'HV' programming. I simply cannot afford the ones currently on the market, and seeing as how I have almost all of the components here already all I need is a PCB made up.
Its pretty tricky, as most USB programmers come with their own software, but I would like to build one that is supported by free programming software (ponyprog, and the ever-faithful IC-prog). Its tricky, so far I am thinking of two options:
1) Standard USB to serial cable (shows up as a com port on win XP, so I can use IC-prog) with a 5-13V DC-DC converter, JDM style. Essentially, just a JDM programmer with a more stable Vpp voltage powered from the USB port. It'll go something like: USB -> Serial -> JDM (with HV supply) and ICSP header. The speed is limited by the PC, and since most USB to serial cables only support up to 115kb/s, it'll not be any faster than the original JDM (it bit bangs the serial lines), however, it WILL be able to program any PIC IC-prog can, by USB. Doable.
2) A custom USB programmer, using a USB PIC, or a PIC with a FT232. Again, with a 5-13V converter on board for Vpp. This would probably require custom software on the PC, which I can't do (not really a software man, except PIC's). very similar to the above, but the speed limit would be down to the PIC and the USB. Which means it can be VERY fast. Downside? it'll require a custom prog on the PC, so unless I can find said software for free, that supports USB (NOT via a com port) and get detailed information on it to write the programmer PIC's software, its not going to happen.
Either way, ultimately I would like a circuit that can operate at as a bog standard USB- serial cable (with high speed capability, around 1.5Mb/s at the UART end), a PIC programmer (with a ICSP header), and possibly the ability to program eeproms. Sounds complicated, but I'm sure it can be done 'fairly' simply.
I'm going to buy a cheap USB to serial cable from ebay to test it with the JDM (with my own Vpp power supply, so the JDM doesn't provide it) and take it apart to see if theres anything 'programmable' in there. you never know, maybe a few tweaks and wires could get it to program a PIC Very Happily.
Experts wanted here, I have yet to find a 'free' USB PIC programmer design that is self powered from USB, external power is not an option (I'm not carrying around a 15v wallwart just for 13v @ a few ma for Vpp). I'm fine with the hardware, any idea's are welcome. The point of this is simplicity, like a 'USB JDM', but also reliable, and useful, and preferably 'quick'.
Regards,
BuriedCode.
Hi,
I've been desgining a dev board for PIC's (18-40 pins DIP's) and although its gonna have bootloading capability, I've been thinking about making a USB programmer for 'HV' programming. I simply cannot afford the ones currently on the market, and seeing as how I have almost all of the components here already all I need is a PCB made up.
Its pretty tricky, as most USB programmers come with their own software, but I would like to build one that is supported by free programming software (ponyprog, and the ever-faithful IC-prog). Its tricky, so far I am thinking of two options:
1) Standard USB to serial cable (shows up as a com port on win XP, so I can use IC-prog) with a 5-13V DC-DC converter, JDM style. Essentially, just a JDM programmer with a more stable Vpp voltage powered from the USB port. It'll go something like: USB -> Serial -> JDM (with HV supply) and ICSP header. The speed is limited by the PC, and since most USB to serial cables only support up to 115kb/s, it'll not be any faster than the original JDM (it bit bangs the serial lines), however, it WILL be able to program any PIC IC-prog can, by USB. Doable.
2) A custom USB programmer, using a USB PIC, or a PIC with a FT232. Again, with a 5-13V converter on board for Vpp. This would probably require custom software on the PC, which I can't do (not really a software man, except PIC's). very similar to the above, but the speed limit would be down to the PIC and the USB. Which means it can be VERY fast. Downside? it'll require a custom prog on the PC, so unless I can find said software for free, that supports USB (NOT via a com port) and get detailed information on it to write the programmer PIC's software, its not going to happen.
Either way, ultimately I would like a circuit that can operate at as a bog standard USB- serial cable (with high speed capability, around 1.5Mb/s at the UART end), a PIC programmer (with a ICSP header), and possibly the ability to program eeproms. Sounds complicated, but I'm sure it can be done 'fairly' simply.
I'm going to buy a cheap USB to serial cable from ebay to test it with the JDM (with my own Vpp power supply, so the JDM doesn't provide it) and take it apart to see if theres anything 'programmable' in there. you never know, maybe a few tweaks and wires could get it to program a PIC Very Happily.
Experts wanted here, I have yet to find a 'free' USB PIC programmer design that is self powered from USB, external power is not an option (I'm not carrying around a 15v wallwart just for 13v @ a few ma for Vpp). I'm fine with the hardware, any idea's are welcome. The point of this is simplicity, like a 'USB JDM', but also reliable, and useful, and preferably 'quick'.
Regards,
BuriedCode.
I don't speak german (but I can sort of get by reading it) but hey, thats why babelfish was invented. This is pretty much spot on what I was looking for, and although I've only skimmed the page, I assume it has PC software, PIC firmware (which may be modded by my own horrible purposes) and it looks like its USB powered. Perfect! I was looking forward to designing my own, but this will save me LOTS of time with software tweaks. I'll opf course email the author of the site with some questions....now wheres my german phrase book..
