{ 20080810
  4x8 LED 7Seg CC display driver (board 3)
  Michael O'Brien
  michael@fmichael.com

  automation:
   propellent /port COM3 _propDisp4x8_1inch_blue_7seg.spin
  20080810 : start
  20080821 : e: sequence working at <2000 speed
             f: split 16 bit word into two
             g: spawn 2 cores for 2x8 bit control word
                rearrange word so 7seg is on byte0 and grid is on byte1
             h: off by 1 crossed wires on 595-0 - fixed
                loading data preceeds switching multiplexer by eight cycle - causing ghosting
                solved by saving prev mux state and only switching when rclk is pulsed
             i: merge 154/138 multiplexing bits - they are the same
                merge 595 rclk/sclk bits, but move rclk from chip0 to chip1 - in line with mux
                slight ghosting on grid because it takes its d/rclk/sclk from another chip
             j: digits displaying correctly, except seg-g on digit 3(blue) for vals 0-on, 2,3-off
                Ghosting solved by holding previous mux value while loading 595
  20081011 : v4: transfered to 7seg blue 1inch 4 digit display board    
}

VAR
  ' shared mem
  long  Stack0[2048]
  byte  mux154a
  byte  mux154b
  byte  prevmux154a
  byte  prevmux154b
  byte  datD595shift
  byte  tempPartAddress
  byte  segAddress
    
  ' Inter processor communication
  byte  tPin
  long  randomNum

  byte semaphore1 

DAT
  ' next line is a RegularExpression match
  digitStore byte 1,9,1,6,1,9,3,6
  cog         long  0               'cog flag/id

'7seg CA CC SURE Electronics blue=ca, red=cc
'    g  f  +  a  b
'    1  2  3  4  5
'
'    -a
'  f|  |b
'    -g
'  e|  |c
'    -d.dp
'
'   10  9  8  7  6
'    e  d  +  c  dp
'

  'gfab.cde                                                                                                                       
  ' 0 1 2 3 4 5 6 7 8 9 a b c d e f g h i j k l m n o p q r s t u v w x y z - +
  segDigit byte 0,1,1,1, 0,1,1,1,  0,0,0,1, 0,1,0,0,  1,0,1,1, 0,0,1,1,  1,0,1,1, 0,1,1,0,  1,1,0,1, 0,1,0,0,  1,1,1,0, 0,1,1,0,  1,1,1,0, 0,1,1,1,  0,0,1,1, 0,1,0,0,  1,1,1,1, 0,1,1,1,  1,1,1,1, 0,1,1,0

'OBJ
'  fmt: "Format"
  
CON
  ' non-spin stamp
'  _CLKMODE = XTAL1 + PLL16X     ' clock speed to high = 12Mhz
'  _XINFREQ = 5_000_000
  _CLKMODE = XTAL1 + PLL8X     ' clock speed to high = 12Mhz
  _XINFREQ = 10_000_000
 ' _delay          = 200_000

  ' pin assignments
  _pin595data     = 7'2
  _pin595sclk     = 5'0
  _pin595rclk     = 6'1
    
PUB Main

  repeat tPin from 0 to 15
   dira[tPin]~~
   outa[tPin]~~' := 1

  ' initialize digit store
  randomNum := 65535

{   8 bit control word
  latest
  0 - d595-a  
  1 - d595-rclk (4x8 led 7seg)
  2 - d595-sclk
  3 - 138-a
  4 - 138-b
  5 - u
  6 - u
  7 - u    
}

 repeat
   'cognew(PushDispControlWord(0), @Stack1)
   
   PushDispControlWord(0)

' 1x8x16 LED Grid
PUB PushDispControlWord(type)
   prevmux154b := 1
   prevmux154a := 1
   repeat mux154b from 0 to 1
    repeat mux154a from 0 to 1
     tempPartAddress := 8 * digitStore[mux154b + mux154b + mux154a]
     'gfab.cde             
     repeat datD595shift from 0 to 7
      ' reverse the segments for blue led's
      segAddress := segDigit[tempPartAddress + (7 - datD595shift)]
      ' place decimal point on 3rd digit
      if(mux154b < 1)
       if(mux154a > 0)
        if(datD595shift > 2)
         if(datD595shift < 4)         
          segAddress := 1

      ' b,a,s,r,d
      PushRegisterStack(prevmux154b,prevmux154a,0,0,segAddress)
      PushRegisterStack(prevmux154b,prevmux154a,1,0,segAddress)      
      'waitcnt(4_100_000 + cnt)
      waitcnt(9_500 + cnt)          
                          
     ' save last multiplex state before switching
     ' loading data preceeds switching multiplexer by eight cycle - causing ghosting
     ' solved by saving prev mux state and only switching when rclk is pulsed
     PushRegisterStack(mux154b,mux154a,1,1,segAddress)       
     prevmux154b := mux154b
     prevmux154a := mux154a
  
PUB PushRegisterStack(a,b,s,r,d)
 ' shift register bits backwards
 PushRegisterBitOnChip(a)
 PushRegisterBitOnChip(b)
 PushRegisterBitOnChip(s)
 PushRegisterBitOnChip(r)
 PushRegisterBitOnChip(d) 
 ' load register in 595
 outa[_pin595rclk] := 0
'      waitcnt(350_000 + cnt) 
 outa[_pin595rclk] := 1
'      waitcnt(350_000 + cnt) 
   
PUB PushRegisterBitOnChip(bit)
 ' write bit
 outa[_pin595data] := bit
'      waitcnt(350_000 + cnt) 
 ' toggle shift clock
 outa[_pin595sclk] := 0
'      waitcnt(350_000 + cnt) 
 outa[_pin595sclk] := 1
'      waitcnt(350_000 + cnt)