DIY edition build October 04, 2011, 10:29:40 am All the parts came in today, so I had to build it right a way!A few points:Ordering:1. The mouser cart was great --- I swapped the header pins for a shrouded header2. The FTDI chip was out of stock, so I got mine from ebayBuilding:1. I had lots of trouble with the FTDI chip. Solder bridges that wouldn't die and some problems with a poor solder joint. This took me a bit of time to work out and I made quite a mess of it!2. Put the VR3 in before C10, your life will be much happier. it is hard to do the other way around3. I had issues with the resistor networks. I don't know why, but I had some a cold solder joint or something. It was causing the self test to fail with wrong voltages, even though the voltages measured fine with a meter. re-soldering the RNs seemed to resolve the issue.Programming:1. I was very confused which firmware to grab. I thought at first that the V4 bootloader was for the V4 hardware. I was wrong.2. read this: http://dangerousprototypes.com/docs/Pro ... programmer it helped a lot to figure out how to load the code.PC software:1. get the ftdi drivers from here if you need them. http://www.ftdichip.com/Drivers/VCP.htmthat was it. now it passes self test and appears to be working. more testing later!Thank DP. Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #1 – October 05, 2011, 01:11:06 pm At times I am still getting bad voltage readings from self test or from the v command. Usually the problem "goes away" with a second try.When measured with a meter the voltages on the headers have been fine. 3.3v seems to be well regulated, the 5v has been the usb voltage (between 5.10 and 5.20), but the pic will report either a higher or lower voltage.two questions.1. Should the 5v regulator give me better regulation or is it just too close to the dropout voltage?2. I have only seen the problem when attached to a powered hub. Could there be some sort of ground loop through the hub that is causing the problem. When the problem is seen, it is usually resolved after measuring the voltage with a meter (battery powered). could it be some stray capacitance or grounding problem? Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #2 – October 05, 2011, 03:15:43 pm The resistors (voltage divider on the 5V line) you have used are prolly 5% so the reported voltage isn't very reliable :) Also the Vref is derived from the supply voltage (IIRC 1% precise)I don't know why the usb hub does give other result, perhaps it needs some time to stabilize? The 5v regulator is very lowdrop (in the region of 100mV) Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #3 – October 05, 2011, 03:18:35 pm I had almost the same problems you had when assembling mine! the FTDI chip is like a magnet for solder bridges! And selecting the firmware was a pain for me too, in the end I got it but there isn't any easy-to-follow guide people assembling their bus pirate.I had problems with the voltages too, but after a few tests I replaced the 5v voltage regulator and it worked perfect.Good luck! Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #4 – October 05, 2011, 04:02:50 pm yeah, the votage divider is not perfect, it reports a little high, that I can live with. The problem I have that I have seen voltages reported from .6v to 6v. I may try changing the 5V regulator and see if that improves it. Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #5 – October 05, 2011, 04:08:08 pm Perhaps a bad solder joint? I would suspect the voltage divider. Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #6 – October 06, 2011, 01:24:39 pm dolabra - thanks for sharing! You're the first to build the DIY version, as far as I know.Hi garyservin - A guide is a great idea. Maybe a wiki page with links to the parts, shopping cart, initial programming instructions, build-up testing tips?Here's the basic of programming:http://dangerousprototypes.com/docs/Pro ... programmer Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #7 – October 14, 2011, 04:55:46 am HI Ian! I've read all the info about the bus pirate before programming it. I didn't have any problem programming the PIC, the difficulty I've found was selecting which version of the firmware/boot-loader use, because almost every single reference about the boot-loader or the firmware is for people who already have the boot-loader installed in their bus pirate.It would be great to have a link in the documentation page, like "building your own bus pirate" or something with the info you suggested (wiki with parts, shopping cart, etc.)!Continue with the good job Ian! Last Edit: January 01, 1970, 01:00:00 am by Guest
Re: DIY edition build Reply #8 – October 14, 2011, 11:39:44 pm all great suggestions, thank you.You can use the bootloader and firmware included in the latest bus pirate firmware download. Last Edit: January 01, 1970, 01:00:00 am by Guest
Topic: DIY edition build (Read 4079 times)
previous topic - next topic
Open Source Hardware