PIC Mapping for <trump>:

data-port: RB0-RB7  Port B van de PIC, alle bits geflipt: RB7 ==> D0	   pic pin 28
							  RB6 ==> D1	   pic pin 27
							  RB5 ==> D2	   pic pin 26
						          RB4 ==> D3	   pic pin 25
							  RB3 ==> D4	   pic pin 24
							  RB2 ==> D5 	   pic pin 23
							  RB1 ==> D6	   pic pin 22
							  RB0 ==> D7	   pic pin 21
adressing strobe signals for the latches:

Port C van de PIC:   RC0 = Timer 1 output. Test LED op PIC board (zoals op het <Puff> board)
			   LED via 1k2 naar GND.			   pic pin 11
                     RC1 = nc   ? PWM output				   pic pin 12
                     RC2 = PWM output - connected to mosfet gate for PWM.  pic pin 13
                     RC3 = nc						   pic pin 14
                     RC4 = A0, latch 0   note board 1			   pic pin 15
		     RC5 = A1, latch 1   note board 1			   pic pin 16
		     RC6 = cannot be used				   pic pin 17
	             RC7 = serial input for MIDI data			   pic pin 18
			   (zoals op het <Puff> board)
Port A van de PIC:   RA0 = A2, latch 2   note board 1     	           pic pin 2
	             RA1 = A4, latch 4   note board 2			   pic pin 3
		     RA2 = A5, latch 5   note board 2			   pic pin 4
                     RA3 = A3, latch 3   note board 2			   pic pin 5
                     RA4 = nc, pull up 4k7				   pic pin 6
	             RA5 = nc						   pic pin 7

 GROUND:								   pic pin 19
									   pic pin 8
 POSITIVE SUPPLY:							   pic pin 20

Note: in the first design we had RA3 N.C. and RA0 connected to A3, latch 3. This appeared to be
      impossible for the PIC's configuration, so we changed it to the scheme given above.
      [ 23.02.2004]
Note: as it appeared impossible to use RC6 as output, we modified the circuit such as to make RA0 (pin2)
      the bit to controll latch 2 [ 28.04.2004]
Software implementation:
Channel = 15 (&H0F)
Note range: (note-on & note-off implemented):
32 to 79 (48 notes)
notes out of the range should be rejected in the PIC software.

The software should have a six byte array to store the contents of the latches: la(0) to la(5)
On reception of a NOTE ON command:
        i = ((note - 32) \ 8)     		' integer divide to obtain the latch in index
        FlipByte la(i)                          ' swap D0,D7,  D1,D6,  D2,D5,  D3,D4
	la(i) = la(i) OR (note MOD 8)           ' set the corresponding bit, preserving existing contents
        FlipByte la(i)				' swap again
        OUT RB, la(i)				' send to data port
        JMP Strobing
On reception of a NOTE OFF command:
        i = ((note - 32) \ 8)     		' integer divide to obtain the latch in index
        FlipByte la(i)                          ' swap D0,D7,  D1,D6,  D2,D5,  D3,D4
	la(i) = BIT RESET la(i),note MOD 8      ' reset the corresponding bit, preserving existing contents
        FlipByte la(i)				' swap again
        OUT RB, la(i)				' send to data port
	JMP Strobing

Strobing:
        ' strobe high:				'         
        select case i
               case 0,1,2
			OUT RC, &Bx111xxxx	' bits 4,5,6 high, x = preserve bits
               case 3,4,5
			OUT RA, &Bxxxxx111	' bits 0,1,2 high
	end select
        ' strobe low:
        ' strobe should stay low for at least 1 microsecond!
        select case i
               case 0
		  OUT RC, &Bx110xxxx            ' bit 4 low  x= preserve existing bits
               case 1
                  OUT RC, &Bx101xxxx            ' bit 5 low
               case 2
                  OUT RC, &Bx011xxxx            ' bit 6 low
	       case 3
                  OUT RA, &Bxxxxx110            ' bit 0 low
	       case 4
		  OUT RA, &Bxxxxx101            ' bit 1 low
	       case 5
		  OUT RA, &Bxxxxx011            ' bit 2 low 
	end select
        ' wait 1 microsecond...
        ' strobe high again:
        select case i
               case 0,1,2
			OUT RC, &Bx111xxxx	' bits 4,5,6 high
               case 3,4,5
			OUT RA, &Bxxxxx111	' bits 0,1,2 high
	end select   
        	
On init, all strobe bits should be high and all notes switched to OFF. The note latches should be cleared.
This should also happen on reception of an all-notes off command:
AllOff:
        FOR i = 0 to 5
		la(i) = 0
		JMP Strobing
        NEXT	

Volume controller:
controller nr. 7
channel 15
The received value for this controller should be output as a repeated PWM signal on pin 13 (RC2) of the PIC.
For parameter value 0, the RC2 pin should be 0.  (no PWM)
For parameter value 127 ,RC2 should be 1. (no PWM)