Xorya Touch

Source code: https://gitlab.com/shaos/xorlib/blob/master/examples/touch.c

In order to read touch sensors (they will be implemented as part of PCB) we need to connect internal pull-ups to those pins then to read we should set pins out, clear pins and set pins in then read a few times (until parasitic capacitor is fully charged through internal pull-up) and analyze (touched pads charge longer):

int tch[4],cc[5],c,i;
ConfigCNBPullups(CNB8_PULLUP_ENABLE|CNB9_PULLUP_ENABLE|CNB10_PULLUP_ENABLE|CNB11_PULLUP_ENABLE);
....
// somewhere in the game loop:
 tch[0]=tch[1]=tch[2]=tch[3]=5;
 mPORTBSetPinsDigitalOut(BIT_8|BIT_9|BIT_10|BIT_11);
 mPORTBClearBits(BIT_8|BIT_9|BIT_10|BIT_11);
 mPORTBSetPinsDigitalIn(BIT_8|BIT_9|BIT_10|BIT_11);
 cc[0] = mPORTBRead();
 cc[1] = mPORTBRead();
 cc[2] = mPORTBRead();
 cc[3] = mPORTBRead();
 cc[4] = mPORTBRead();
 for(i=0;i<5;i++)
 {
  c = cc[i];
  if((c&BIT_8) && tch[0]==5) tch[0]=i;
  if((c&BIT_9) && tch[1]==5) tch[1]=i;
  if((c&BIT_10) && tch[2]==5) tch[2]=i;
  if((c&BIT_11) && tch[3]==5) tch[3]=i;
}

Xorya-touch in action (connected to TV and PICKit3):

for now it shows static image 320x200 with 2 half-frames (it's drawn as 160x400 with interlace):

This is the next prototype of #XORYA - extremely low cost game console on PIC32 with capacitance touch interface where 4 pads connected to RB8, RB9, RB10 and RB11 (and there is a ground ring around them):