The example shows the connection of a device from the dsPIC30F family to a standard PS/2 keyboard. It is important to note that all pins of the PS/2 keyboard connected to the dsPIC30F device are connected to the power supply by the pull-up resistors. The realization is carried out by using the mikroPascal compiler for dsPIC30F microcontrollers.

program ps2_test;

var
 keydata, special, down : word;
 txt: array[20] of char;
 
begin
  nop;
  ADPCFG:=$FFFF; // PORTB to be digital on 30F4013
  keydata := 0;
  special := 0;
  down    := 0;
  
  Ps2_Config(PORTC, 14, 13);
  Uart1_Init(9600);
  txt := 'You can type now!';
  Uart1_Write_Text(txt);    // Ready

  while true do
  begin
    if Ps2_Key_Read(keydata, special, down)=1 then
      begin
        if (down<>0) and (keydata = 16) then
          begin
            Uart1_Write_Char(0x08);
          end
        else if (down<>0) and (keydata = 13) then
               begin  // Enter
                 Uart1_Write_Char(13);
                 Uart1_Write_Char(10);
               end
             else if (down<>0) and (special=0) and (keydata<>0) then
                    begin
                      Uart1_Write_Char(keydata);
                    end;
      end;
    Delay_ms(1); // debounce
  end;
end.