[slimneill]

I have a used Mitsubishi MPG that I would like to use for my CNC machine, on the back of the MPG there are the following connections:

12V+
12V-
GND
A
B

When we move the MPG one detent we get the following responses across A-B:
3V+, 0V, 3V-, 0V, 3V+…

Is this safe to run on the KFlop? I don’t want to fry the KFlop by sending too high of a voltage, I know the Kflop IO’s say 3V tolerant, but I’m sending 12V to the MPG, is this standard for all MPGs to send back a 3V signal? I’ve never tried to wire one before?


I'm planning to use the MPGSmooth.c to fun the MPG, If i understand the code correctly I only need 2 inputs QA, QB for the MPG and the rest are inputs for the various buttons typically found on a pendant.

Thanks,
Dan

[TomKerekes]

Hi Dan,

Check the A signal relative to GND and also the B signal relative to GND while not connected to anything rather than from A to B. Seems a bit odd to require +/- 12V supplies but if each of the outputs each stay between 0 and +3.3V it should be ok.

Yes you only need 2 inputs for the MPG encoder motion. Most MPGs are slow enough that a program like MPGSmooth.c can be used to count the transitions in software using any IOs. The other option is to use an unused KFLOP Hardware Encoder Input and use the MPGSmoothHardwareEnc.c example.

You should be aware that some of the KFLOP inputs (first 8 on JP4 and JP6) have 150 ohm pull down resistors. If you connect to those (which would provide good termination) then you would need to check that the MPG is able to still drive them above 2.8V.

HTH
Regards