Re: Unusual Paymar adapter

[bieling@terra.es (Jorge ChB)]

Michael J. Mahon <mjmahon@aol.com> wrote:

> In going through some boxes (!), I found an unusual Dan Paymar adapter.
> 
> It is a "daughtercard" that plugs into a ROM socket (probably the
> character ROM), and has on top two 24-pin sockets (for other ROMs),
> and also two wires about 4" long going to a small socket adapter
> having a 16-pin plug on the bottom and a 16-pin socket on top, with
> a 14-pin 'LS74 plugged into it.
> 
> The daughtercard also has two ICs, a 7404 and a 7410, plus a
> decoupling capacitor.  The manufacturing date code on the
> card is 7639, so this is a *very* early mod.
> 
> I'm guessing that the 'LS74 is used to switch between the two
> ROMs, but I have no documentation or software.
> 
> Does anyone know about this?

I had a "Dan Paymar's lowercase adapter", but iirc it was little more
than a ROM that replaced the onboard char. gen. ROM.
This one you've found must be a "deluxe" version or something.
My best guess is that the extra circuitry is there to engage somehow
alternate characters when in inverse or flash modes..?

-- 
Jorge Chamorro Bieling