HD44780 is it programmable/OTP

[sambo]

I am wondering if this chip is a microcontroller or just PLD
I have an LCD (LM16255) with it and OKI M5259 but I can't get it to init
into 4-bit mode. I know some LCDs don't support 4 bit mode
but I thought , those are only compatible with 44780.
Any Ideas?

Thanks Sam.

 

[David L. Jones]

I am wondering if this chip is a microcontroller or just PLD

It's a custom microcontroller with some glue logic like shift
registers, latches and timing stuff.
Take a look at the block a diagram in the datasheet to see what's
there.

I have an LCD (LM16255) with it and OKI M5259 but I can't get it to init
into 4-bit mode. I know some LCDs don't support 4 bit mode
but I thought , those are only compatible with 44780.

The OKI M5259 is not 44780 compatible, see the datasheet here:
http://www2.okisemi.com/site/datasheets/msm5259.pdf?var_docid=msm5259&var_intro=Intro-7230

Dave.

 

[Ben Jackson]

I am wondering if this chip is a microcontroller or just PLD
Any Ideas?

Not sure what you are trying to accomplish, but Microchip and Atmel
(and others, I'm sure) both offer microcontrollers with integrated
LCD segment drivers (up to hundreds) if you are looking to make a
custom LCD product.

The HD44780 probably has a ROM mask for the fonts, since most of the
datasheets I've seen include a workflow for designing your own font
and getting a batch of controllers made.

 

[Sambo]

It's a custom microcontroller with some glue logic like shift
registers, latches and timing stuff.
Take a look at the block a diagram in the datasheet to see what's
there.

So more or less fixed application(s). I was wondering if maybe this one
is loaded it with modified software without 4 bit support.
Frustrated wasn't thinking clearly...... again.

I guess it is back to trying to use a shift reg for my getup.

Cheers.