lcd problem, core debug

[cookd]

Hi,

this is my first post... I've build a core module from mike, loaded mios into pic but no LCD messages displayed (if I send a clear to LCD from miosstudio debug I get a couple of vertical lines on and off for a while then nothing), backlight is ok and could be dimmed, contrast trim is halfway.

LCD is 20x2 chars branded Powertip PC2002LRS

pics and pinout, that seems compatible, are in the attachments

not sure about the onboard chips compatibility.. any suggestion/experience to share?

btw... I've uploaded LCD benchmark... but nothing displayed either..

thanks in advance 

stefano

[cookd]

ERRATA:

not sure about the onboard chips compatibility..

CORRIGE:

I know from the powertip website that the controller is

S6A0069X* : KS0066U, or equipped with equivalent IC

is this good? do I need to load additional software on pic?

thanks

stefano

[dj3nk]

It has to be a HD44780 compatible LCD.

look here for other supported lcds:

http://www.ucapps.de/mbhp_lcd.html

greetz

[seppoman]

the KS controller is HD44780 compatible. Virtually any text LCD is compatible nowadays that has 16 pins connector (or sometimes 14 plus 2 separate for backlight) and matching pin names. So this can't be the reason. Most LCD problems of midiboxers are caused by wrong wiring and/or bad soldering/shorts, so first doublecheck everything again.

S

[cookd]

double checked... problem remains!

rewired Jim Henry style... problem remains!

lcd interconnection test loaded... voltages ok, no bad solders, no shorts

disconnected backlight... problem remains

probably I've to disconnect the midiboxer  :P

...seriously, could be a faulty LCD? on startup I only see poor signs of life, some blocks/lines feeded then go off and remain off...

cheers

s

[seppoman]

...seriously, could be a faulty LCD? on startup I only see poor signs of life, some blocks/lines feeded then go off and remain off...

the normal startup would be to have the first line (full normal height of the first text row) full of blocks. It should look like the last one on this picture:

So if you mean by "some blocks/lines" that only some intermittent parts if the display go black, perhaps it is broken. On the other hand, the subsequent clearing of the display is a sign of life.

S