Alphanum OLED display driver

MIDIbox SID
1

Hi,

I worked a little to get my OLED display working with the SID firmware.
It didn’t work with the out of the box MIOS driver,  my oled remained totally black.

Here is the OLED i have.

It’s now working wotj the following modifications.

What must be done is to enable Custom LCD in main.inc USER_Init function.

  ;; CUSTOM LCD
  movlw    0x07
  call    MIOS_LCD_TypeSet

Then replace app_lcd.inc by the one attached here in “midibox_sid_v2_044/src”.

It’s based on the file found  with some init sequence and timing modifications.

Best,

Xavier

 

[app_lcd.inc](< base_url >/applications/core/interface/file/attachment.php?id=12727)

app_lcd.inc

2

Hi Ixox,

great you got it working and that the old post was maybe of some help!

I’ve still not fully understood what causes the incompatibility - i need the exact code as posted for the 4x20 VFDs, but found it only out through trial and error - it would be so nice to have a general solution working with the standard CLCDs, OLEDs and VFDs :-).

Did you get any more insights when hacking your driver?

Many greets!

Peter

 

3

Yes thanks for you old post. Very usefull :slight_smile:

I’m not sure the MIOS clcd driver initializes perfectly the 4 bits mod.

http://svnmios.midibox.org/filedetails.php?repname=svn.mios&path=%2Ftrunk%2Fmios%2Fmios_clcd.inc

Look at page 46 of the HD44780 spec :
https://www.sparkfun.com/datasheets/LCD/HD44780.pdf
The app_lcd.inc i attached follows it more strictly.

Also i think the clear() commands should have a wait of 2ms.
It’s not very clear in the spec as the 1.52ms is mentioned for the “return home” function, but that was a bloker for my OLED to work, and it’s what LiquidCrystal (HD44700 famous library) does.

Best,

Xavier

1 Like
4

Thanks for your insights and many greets!

Bye,

Peter