Using a cheap oven to bake "chips"
The old man version of the Pesky Padauk Programmer is almost dead. Although in a previous blog and video I was able to talk to the STM32 and thus load the firmware onto this board - I was not able recognise or program any Padauk Chips <grrrrrr>.
In a parallel approach (multitask!) I bought a cheap oven and started to look at ways of monitoring/controlling the temperature (which was the subject of yet another previous blog and video) with the aim of baking SMD parts onto a PCB to maybe make a working programmer.
After testing the oven's capabilities, I opened up the stencil, scraped some solder paste onto a board and then spent a happy half hour carefully placing components onto the board.
The oven fired up and although it was clearly a bit "half-baked", the rig worked well and a few minutes later I had my first cooked PCB.
However, we have been here before and so it was with some trepidation that I loaded up the firmware, stuck in a padauk (PFS154) and firstly tried to recognise and then program the chip.
Success! And now we look at how to program these strange exotic beasts to do some useful work around the place instead of sucking up all my time!
Hi after reading your stuff about building the Padauk programmer I was inspired to try it myself and ordered the bits.....
ReplyDeleteI feel your pain re building this programmer :-(
As one who's old eye are not what they used to be the soldering is tricky and identifying some of the components is challenging!
I eventaully got the board to work and can program even the 6 pin PMS150C 3 cent chips , BUT needed to use the latest version of the easypdk programmer software to recognise that chip.
I staged the build by limiting the initial number of components to the bare minimum for the processor and (via the SWD pins) put a bit of ARM assembler code to flash the leds which This gave me confidence that at least the processor was working !!!
I then added the other parts spread over a couple of days!!! and tried add the firmware with no success.
Eventually I found that the issue was the USB connector and after 2 attempts to replace it gave up on the micro USB and bodged a connection to a cable , et voila it loaded the firmware via DFU....
The easypdkprog software recognised the board but when I tried to probe a PFs154 chip no dice ...
Looked at the voltages on the board and they were incorrect so eventaully (over a couple more days) found that a couple of the resistor and cap values were wrong (my fault) and after changing them it worked.
The 6 pin chip is programmed to act as the the clock for a 6502 project whic is cheaper and simpler than a crystal oscillator setup :)
Sounds like a journey for both of us! Well done on persevering...I’m now trying to learn the coding side. I wish I had started with the reflow oven idea!
ReplyDeleteHello. Thanks for the very good review. I wanted to ask in the photo you showed the board second from the right as the most successful one. Where can I find Gerber for this board? I found it on github, but there is still an old version, (first on the right on the table)
ReplyDeleteThe "Lite" version gerbers are found here: https://github.com/free-pdk/easy-pdk-programmer-lite-hardware
DeleteIt's been my most successful version, particularly if you get your PCB manufacturer to solder the smd components for you (particularly the usb connector which is a bit of a trial!).
Good luck!