Buttons don't want to work.....

Testing/Troubleshooting
1

I got a strange problem with my buttons on my first midibox (the second identical one works perfectly).

My buttons don’t want to work except the menu-button.

But this works as snapshot button. Means it works like pressing menu button and snapshot button together.

The LEDs blink at boot time as normal. So I think the clock wires are ok.

But when I send a midicontroller that is assigned to a button, the corresponding LED will not light!

At first pressing with the finger on the PCB sometimes helped. So my guess was a soldering or other contact problem. But I could not find it!

After soldering all suspected (and some more) contacts again even the little fingerpress solution would not work anymore…;-(

Things have done:

  • measuring all contacts and wiring (RCLK, SCLK, IN)

  • changing the controller

  • changing the software

  • changing the first 74HC165

  • looking, searching, looking

  • bite in the table…

Now I disconnected the wiring from mother to doughterboard (layout from greg). So only the first shiftregister is connected. It’s serial input to the next SR is free.  

But even then only the menu-button works in te way I discriped. I took a look in the source code (button.inc). But that is a) very difficult to read, b) would not explain the behaviour, so far I understand it.

I have no scope to see the bits. And what happens there.

Please tell me all your suggesten. Even if they are very unlikely or stupid. I have no ideas anymore.

2

I got an idea. It shall be possible to use an other 595 shiftregister connect its serial in with the serial IN pin of the PIC, as well es the clock signal.

With 8LEDs it should work as a bitscope.

3

Just for interest: Problem solved.

Pin20 of the socket was brocken. I noticed that while soldering a wire directly to pin 20…ARRGGG.

The little pressure while meassuring are enough for contact, so that I meassured all ok.