How to test Shiftregister pins?

[Thomas]

Hallo!

I have a problem with the shiftregister of one PIC.

The DIN-shiftregister does not work.

When I press button 8 on the first shiftregister it is like pressing all 40 buttons, but pressing onother button has no effect.

(The DOUT register do not work, too.)

I have no scope, so I messured the voltage on pins D3 and D2 with a multimeter. I get 0.16V and 2.55V. BUT on the other pic that works I messure 0.08V and 3.5V.

I changed the EQU of the pins in the MIOS-src, compiled a new MIOS with interchanged D2 and D3 and I messured 2.55V and 0.16V as expected. The pins have changed.

All connections seems ok, and even worse, it had worked last week!

Something must be broken and I could find it. I replaced the 165, too.

[TK.]

Hi Thomas,

here are the detailed troubleshooting instructions:

-> http://www.midibox.org/dokuwiki/doku.php?id=din_module

Best Regards, Thorsten.