this could be a problem with the SC connection, this is a clock signal which shifts the data through the serial chain.
If this signal is not working (e.g. due to a short), the core will always get the state of the first pin in the chain, therefore you see a lot of MIDI events triggered by a single button.
I’ve written an application which allows to debug this, it can be downloaded from http://www.ucapps.de/mios_download.html, search for “srio_interconnection_test_v1”
Thanks Thorsten, I saw the main.asm and I measured the SC and RC voltages directly from the DIN module, and SC=0V. Then I measured this pin in CORE without the DIN and SC=0V again. I looked for a short in the CORE but all is OK, what could be, Thorsten? Thanks you again.
It could be a short which is hard to find. You can ensure that the RD3 pin (pin #22) is still working by lifting it from the socket, so that it doesn’t have contact with the PCB anymore. Is it possible to switch between 0V and 5V now?
Well, I deciced to make the CORE PCB again, I can’t find the short. I realized that I forget the bypass caps on the bottom side!! :o ::)… Thank you very much Thorsten!!!
Short question: did you also create the DOUTX2 module? Is it already connected to the core? Because somebody just reported, that this PCB has two bugs, they lead to a short circuit
I would like to comment something, I finished to make another CORE, and I have the same problem, the voltage between SC and groud is 0V (really 0.26V), this means that the PIC internally has a problem caused by a short? (the DINx2 connected to the CORE had a short). Will this affect the PIC performance some day?
