Re: videx video card or getting lowercase display on a II+

[David Wilson <mcs6502@gmail.com>]

On Jul 7, 9:49 am, Knut Roll-Lund <kr-l...@nogarbage.online.no>
wrote:
> In basis I'm just out to get lowercase (on the display) for my II+. So I
> though an 80col card would do the job. My II+ is the RFI version so an
> option would be to just burn eprom and replace the character generator.
> I have a programmer and I have suitable eproms. What I miss is a clear
> description of what modifications I need to make. - You need to add an
> extra bit for the decoding don't you? Or does the RFI version bring all
> the necessary bits to the character generator for it to handle also
> lowercase?

The Rev 7 and later boards (including your RFI board) do have all the
required lines connected to the CHARGEN socket - DL6 to A9 (pin 22)
and DL7 to A10 (pin 19). On the output O7 (pin 17) is the FLASH ENABLE
signal.

GSE Reactive sell a chip with lowercase (see
http://www.gse-reactive.com/product_info.php?products_id=163 where you
can also download the data to do DIY programming).

I replaced my 2316B ROM with a 2532 and used AN3 (via a length of
wire) to select between two different character sets.