[s1mp3-dev] RES: LCD Port from FW

[Chris Double]

On 9/19/06, Mateus Del Bianco <mateus at delbianconet.com.br> wrote:
> what you need is the port, the other lcd pin to set the lcd to accept the
> incoming byte as a command or as data...

So if the port is F4, and the bit controlling whether it is data or
cmd is bit 2 then the following tells the LCD that it should be in
command mode:

  in a,(0xf4)
  and 0xfb
  out (0xf4),a

the 'and 0xfb' sets bit 2 to 0 = command mode. To set to data mode:

  in a,(0xf4)
  or 0x04
  out (0xf4),a

This sets bit 2 to 1 = data mode.

In command mode, you write to memory address 0x8000 with the command:

  ld a,0x00
  ld (0x8000),a

In data mode you write to memory adress 0x8001 with the data:

  ld a,0x00
  ld (0x8001),a

I assume the cursor position that the data is displayed at is
automatically updated when 0x8001 is written to?

Does that sound right?

Chris.
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