MIN progress

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So I broke my Pokémon Mini (MIN) trying to solder some wire-wrap onto the LCD connector. Wire-wrap was of course as big as each pin and pitch was only 0.5mm, so yeah… That didn’t work out.

I was going to check out the display signals while actually seeing the display work. Alas, having broken something in the connector (possibly related to me melting it with my soldering iron *oops*), I took the connector off (0.5mm 29pin FFC with connection on PCB side [down, below]), soldered the darn wire-wrap onto the PCB pads — and managed to halfway rip off CN3-23 in the process *yay me* — and used my scope to make some waveform shots. This is the result:

CN3-23 – #RD?
CN3-24 – #WR
CN3-25 – A0
CN3-27 – #CS
CN3-28 – 18.7 kHz square wave (CL?)
CN3-29 – static 0 (FR?)

My scope traces only clearly show A0, #WR, #CS and CL. #RD is always 1, FR is always 0. However, the SED1565 datasheet really put things into perspective. The native LCD FFC pinout closely matches the condensed pinout found on CN3 resp the MIN LCD FFC. Since only two signals weren’t clearly identified and their default polarities match, I think this is a good fit for now. Providing an external clock and external FR might also be useful for the MIN to do cool LCD effects as well as turn the LCD off when in power down mode.

Connector and signal names as in my preliminary MIN Mainboard schmatic (which I just updated). BTW, the boost converter (StepUpConverter in schematic) works nothing like what was in the v1.0. Pin PG is an enable that will take the output voltage VOUT from ~1V to ~3V. Pin EN is actually used to turn the boost converter off again, I think (odd voltages on that pin…). I was working on a proper schematic for that sub-board itself anyway, which is why I did not bother updating the schematic for v1.1.

Incidentally, the display not being there somehow prevented the MIN from turning off. Or maybe I just wasn’t patient enough (had to press the buttons using tweezers). Or maybe I broke the #RD pin by shorting it and the MIN entered an infinite loop trying to read from the display? I’ll probably never know.