BBS’ing With The Epson PX-8 Geneva

July 28, 2011July 28, 2011Retrocosm 1 Comment

I’d hoped to acquire an acoustic coupler to use with the Epson PX-8 however it wasn’t to be. Plan B involved connecting up an external modem and I therefore needed some software that would allow me to communicate with the US Robotics unit that I have, Mex from NightOwl Software was the obvious choice.

Using this guide I was able to determine which files I needed specifically for the PX-8 which were as follows:-

MEX114.COM
Assembling MEX PX8 Overlay
MLOAD25.COM
MXO-PX8.ASM
MXO-SM14.ASM
ASM.COM
MEX.HLP

The MXO-PX8 overlay is I believe written specifically for the Epson Multi Function Unit which has a built in modem and sits below the PX-8 connecting via the system bus. It is therefore also necessary to include a generic Hayes compatible overlay if you need to communicate via RS232 with an external modem.

Generating MEX For The PX-8

I used Filink to move all the files that I needed across to the PX-8 and saved them on disk with the TF-20 and used ASM.COM to assemble the overlays. Using MLOAD you can then generate a MEX executable tailored specifically to your PX-8/Modem set up.

Epson Cable 724

In order to connect a modem to the RS232 interface on the PX-8 you need the Epson 724 cable, which is mini din to DB25. Fortunately one of my PX-8’s came with this cable and it’s not to be confused with the similar looking 725 cable which is a null modem version.

Px-8 & U.S.R. Modem

So then the moment of truth, what chance this would all work? I decided I should try and find a dial up BBS other than mine own to try. Wgoodf’s recent blog entry pointed me in the direction of the Plasma Sphere BBS which I didn’t have any luck with but this did lead me to the Arcade BBS.

A nice feature of MEX is you can use either ‘Call’ or ‘Dial’ to initiate the call, the latter will allow you to drop back into the command line and fire up other software if necessary, Kermit for instance. I stuck with ‘Call’ initially and it worked! Sort Of. Clearly there are some issues, I’m guessing buffer overruns but I’m sure these can be ironed out.

So here’s a video of me connecting to the Arcade BBS with my Epson PX-8 using Mex:-

(Update, I restricted the RS-232 port to 300 Baud and tried again with better results and have therefore updated the video, ahhh 300 baud, those were the days.)

Epson PX-8 Terminal

July 16, 2011Retrocosm 1 Comment

I’ve been messing around with some terminal stuff today. I have almost no experience of terminal software so it’s not coming naturally to me. What I had hoped to achieve was to use the PX-16 with its clearer screen as a dumb terminal for the PX-8.

I don’t yet have a serial cable that fits the PX-16 so I’ve been experimenting with the PX-8 hooked up via RS232 to my Windows 95 box. By luck one of the PX-8’s I have came with a pre-configured copy of Kermit. I downloaded Kermit for Windows 95 and set about trying to get them to talk to each other. After a bit of fiddling I managed to get the PX-8 acting as a sort of dumb terminal for the other box.

What I really want is to do this the other way around but due to my ignorance of the subject I don’t know if that’s even possible, whether you can control a CP/M box via DOS or if you need two CP/M based machines. In my mind the terminal is just acting as screen and keyboard for the other machine but it doesn’t seem to be working that way. Still early days and some reading required.

This is just a quick video of me changing directory and listing the directory of the Windows 95 machine on the PX-8.