Keith Howell wrote:

> I recently bought two HD44780 LCD modules.
> The size indicated 16 chars x 2 rows.
> However, only the top rows appear to work.
> The bottom stays blank.
>
> Do 16x1 modules use the same glass as the 16x2 ones,
> but have different driver circuits?
>
> I can see an HD44780 and a HD 44100 but no part number.
> I'm reasonably familiar with driving HD44780 style devices,
> and so fairly confident it is initialised properly.
> I've had text appearing on row 1, but the text for
> row 2 doesn't appear where it should.
>
> Yours curiously, Keith.

You are probably writing in the RAM section 'between' the rows.Some genius decided that having
linear addresses for LCD's are
way too easy, so now we have to deal with invisible rows.

Try writing to the 'third' line.

--
Friendly Regards

Tjaart van der Walt
mailto:tjaart@wasp.co.za

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