**SOLVED** Duinomite PS/2 support

Started by ctigs, June 23, 2015, 09:50:07 PM

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Does the Duinomite (not mini, mega, or emega) use a different method of working with the PS/2 keyboard or all versions of the Duinomite the same when it comes to the keyboard port?

Also, when I try to flash my duinomite with the DM basic from github the board bricks.

I can flash it with MMbasic 4.5 and it loads, with Z80 sim and it loads, but I can not get it to go back to factory firmware.

What could I be doing wrong?

My Duinomite doesn't work with the PS/2 keyboard no matter what firmware I use.  I can use the USB terminal to work with the board, but have been unable to make the keyboard function.

I treied external power, I did a continuity test of the keyboard signal paths from the KB socket to the PIC chip, good solid connections, no opens, no high impedance, and no shorts to other lines.

The vendor I got the board from says it's software.

I have a mega as well, and all the same software works on the mega with the same monitor, power source and keyboard.

Anyone got any ideas?


I compared the schematics of the Duinomite and the Duinomite MEGA and they use exactly the same pins for KBD DATA and KBD CLK. Also the pullup resistors are the same. If you connect the 5 V power and the ground it should be exactly the same. Maybe the capacitor to the shield of the keyboard cable can help also.

What I remember from the past from connecting a PS2 device to a PC is that you should be carefully and you should not do a hot-plugging. From the schematics I see that also on the Duinomites the connection is directly on the PIC32 processor. So I think also here you should not do any hot plugging on the keyboard.



Yes, good point.  But I don't hot plug PS/2 devices.  They don't have longer power or ground pins, and are not designed for hotplugging.

I still don't know why the .HEX file for the original firmware breaks the system.  The bootloader remains intact but the basic doesn't work.  No USB connection, no VGA, no yellow LED.

I'm sending the board back to the vendor for replacement (they FINALLY agreed to replace it)

I'll have to try the .HEX file on the mega and see if the file is damaged or my Duinomite was bad in more ways than one.

I'll post again when I have more info.


OK, figured out the keyboard problem.

The PS/2 socket on the I/O board was wonky.

I could get continuity with my microprobes via the socket but it didn't actually make contact with the keyboard pins.  Don't say it was something I did, it was not working before I probed it.

This problem is now solved!