HP30b flashed with WP31 no longer responding

[mfleming]

Oh frabjous day! Callooh! Callay!

Well, enough of the Lewis Carroll. I hold in my hands a working WP 31S awaiting keyboard stickers (A task for tomorrow so as not to ruin a perfectly fabulous day by putting them on crooked or something). I also managed to resuscitate a WP 34S I thought I ruined whilst trying to connect serially to the emulator via an FTDI cable. The solution to my original problem ended up being the pogo-pin programmer assembly.

On reflection, my earlier jury-rigged setup was a disaster waiting to happen and an outright miracle it succeeded in flashing two previous calculators (poor signal and power connections, a real "No duh!" problem source). The pogo-pin assembly currently lacks the spring clip to hold the assembly to the calculator body. Some electrical tape to hold the assembly in place and light thumb pressure was all that was needed to get MySamBa to reflash the units.

Well, in embedded development the old saying is; The shortcut is the longest way around. Best to spend the extra time putting together a well built test rig. I'd still like to get the JTAG approach working though, since it's a good solid connection and the JTAG unit automatically matches I/O lines to the target voltage. Perhaps then I can play with the various branches and variations available.

For anyone interested, I used Mill Max spring pins (P/N 0914-0-15-20-77-14-11-0) from Newark Electronics (they partner with element14 in Europe). The pins have a short body (0.37"/9.4mm) and a long throw (0.1"/2.3mm). The PCB termination end of the pin fits snugly into a 2x3 ribbon cable header. The 2mm header and 1mm ribbon are also available from Newark.

Thanks to everyone for responding, I do appreciate the help. I look forward to the next re-purposed host, if any. Perhaps an HP 17bII+ or 35s with a custom replacement PCB?

Who knows,
~Mark