Software for Timex RS232 interface

[BrunoFlorindo]

I'm not sure if this interface can also be used in the ZX81, but I think it can:

http://cgi.ebay.co.uk/Timex-RS232-Inter ... dZViewItem

The problem is, the Portuguese seller says in the description that it has been tested and works o.k. But when I asked him how did he test it if there's no software, he told me he used a voltimeter and a few pokes, which he can't remember anymore because he sold the manual with another RS232 interface. It all sounds like bs to me, to be honest.

My question is, does anyone have the software for this interface? I can't find the software anywhere.

[RWAP]

No sign of the software anywhere, but the manual appears at:
http://timex.comboios.info/tmxtechrs232.html

[BrunoFlorindo]

Thanks Rich.
Oh well, how good is an interface without its software? I guess I'm gonna let this one go.

[BrunoFlorindo]

Hehe, I went to Portugal a couple of months ago and found my cousin already had one. He gave me the interface!!! The interface, software and manual have been preserved. If there's any interest I'll look for the links so you can download them.

[Littlejohn]

I would be interested in the software and manual.

[BrunoFlorindo]

Glad to see someone's interested!

My friend José Leandro helped me (once again) and photographed and documented everything. The interface traveled to Spain and back, but I'm happy. Here's links to the software, manual, schematics and photos:

http://www.speccy.org/hardware/hardware ... mex-i.html
http://www.speccy.org/hardware/hardware ... fotos.html
http://www.speccy.org/hardware/hardware ... mas-i.html
http://www.speccy.org/hardware/hardware ... acion.html

http://www.speccy.org/trastero/2008/081208/Timex.htm
http://www.speccy.org/trastero/2008/081 ... mputer.zip

The English translation was made by Johnny Red (a Portuguese friend). If there's something specific that you need to know I can take a look at the Portuguese original and I'll help as much as I can.

[siggi]

Hi Bruno
IMHO there are 2 minor errors in the schematic: the PRESET inputs of LS74 (pin 4 and 10) are undefined (both are inputs, but no one drives them). They are probably also connected to VCC. And the symbols used for C9 and C10 are wrong (resistor symbol instead of capacitor).

Funny: this RS232 interface does not contain any uart chip, only a "parallel" port for data bits D1 and D7. So the Z80 has to do the bit shifting in software!

Siggi

[sirmorris]

That's a very comprehensive preservation!

Congratulations

@ siggi : don't be surprised, look what they made the poor z80 do on the zx81 A bit of uart duty is nothing

[BrunoFlorindo]

Jose Leandro asked me to make a post for him. I'm going to translate it and will be posting it soon. It explains why the schematic was done that way.

[BrunoFlorindo]

Here's Jose Leandro's reply to Siggi's post:

[quote=""siggi"]the symbols used for C9 and C10 are wrong (resistor symbol instead of capacitor).[/quote]

Jose Leandro: I've changed the symbols and it now shows capacitors. The program that I used to create the Eagle file didn't had a capacitor that looked like the original, that's why I used a resistor instead. It was also done that way to make sure the board would have the same dimensions as the original.

the PRESET inputs of LS74 (pin 4 and 10) are undefined (both are inputs, but no one drives them). They are probably also connected to VCC.

Jose Leandro: Yes, they should be connected to VCC, but since I didn't find a line/signal, I decided to leave it like that.