'27-4-00
'Test code for HG12605 128*64 graphical LCD display

'Pin allocation
' control signals
Di Alias P1.4                           '1 data, 0 instruction
Rw Alias P1.5                           '1 read, 0=write
E Alias P1.2                            'clock
Cs1 Alias P1.3                          'active high select left half of display
Cs2 Alias P1.0                          'active high select right half of display
Res Alias P1.1                          'active low reset
' data lines
Dbus Alias P3


'General method of communication
'WRITE - set up control lines, raise E, write setup data, lower E, repeat
'READ  - set up control lines, raise E, read data, lower E, repeat

'INITIALISE DISPLAY
'Reset display and initialise lines to resting state
Res = 0                                 'reset active
Di = 0                                  'instruction
Rw = 1                                  'read
E = 0                                   'clock low
Cs1 = 0 : Cs2 = 0                       'deselect both chips
Waitms 10                               'delay for a while, I assume non-critical

'Un-reset display
Res = 1                                 'release rest line
Waitms 10                               'allow it to come out of reset (may not be necessary)s

'Turn display on WRITE 00 00111111
Rw = 0
Di = 0
Cs1 = 1 : Cs2 = 1                       'select both chips
E = 1                                   'clock high
Dbus = &B00111111                       'setup data for falling edge
E = 0                                   'clock in data

Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop 'just in case

'Set page (X address) (to zero)
Rw = 0
Di = 0
Cs1 = 1 : Cs2 = 1                       'select both chips
E = 1                                   'clock high
Dbus = &B10111000                       'setup data for falling edge
E = 0                                   'clock in data

Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop 'just in case

'Preset column (Y address) (to zero)
Rw = 0
Di = 0
Cs1 = 1 : Cs2 = 1                       'select both chips
E = 1                                   'clock high
Dbus = &B01000000                       'setup data for falling edge
E = 0                                   'clock in data

Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop 'just in case


Dim Num As Byte
Dim X As Byte
Dim Xx As Byte


' Pre-setup control lines (they don't need to change)
Rw = 0                                  'write
Di = 1                                  'data
Cs1 = 1 : Cs2 = 1                       'leave both chips selected (no reason why not)

Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop : Nop 'just in case



'Now write a moving patten into the columns
For X = 0 To 63 Step 8
 Num = 1
 For Xx = 0 To 7

  E = 1                                 'clock high
  Dbus = Num                            'setup data for falling edge
  E = 0                                 'clock in data

  Rotate Num , Left                     'move pixel down one for next line
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