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FantomXR

Help needed for implementing 3rd shift register for keyboard scanning

2 posts in this topic

Hey people,

here is the problem:
FATAR has changed the diode-matrix of their keybeds recently. So the DIO-matrix is not usable for those keybeds anymore. I want to get it running and of course I'm happy to design a new DIO-matrix and of course post it here so everybody can use it.

So... I'm not 100% sure about the diode-matrix yet. In the old diode-matrix both keyboard sides (left and right) had separate rows. So the left side had 8 rows, the right side had 8 rows:
Matrix_88.gif

Look at this pictures. With "rows" I mean T0-T7. 

In the new diode-matrix it looks like both sides use the same rows. Because if I plug in a new keybed (via an adapter) into a DIO-matrix (which I did many times before with old keybeds though old diode-matrix) it outputs correct values from a-1 (lowest key) till middle-C. With the next key C#3 the left side starts. But C#3 outputs a-1. Further tests confirmed my assumption, that both sides share the same set of T0-T7. 

So that means: I need a shiftregister more than is available on the DIO-matrix. At the moment I have T0-T7 connected to the 8 inputs of the HC165, MK&BK are connected to the 16 outputs of the two HC595s. So in total I can connect 64 keys to the DIO-matrix. I now want to add another 595 to connect the last keys. Of course connecting the 595 itself is easy and done quickly. But I need to adapt the code and what I've tried so far was not working. I need to add a dout_sr3 to the code...

Any help?? Maybe @TK. could point me in the right direction!

Thanks people!

Best,
Chris

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No one? Any help would be very appreciated! 

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