TRS-80 PC-2 Emulator

NOTE I seriously want to get more in to depth on the subject on this page. I did use this calculator intensively and still know quite a lot about it to make an interesting set of pages. This page might move to my calculator section eventually.
Also, a lot of people are asking for source code. I haven't yet decided what to do, I might release if but I'm not sure. It's still quite unfinished and it's written in Pascal (which was a logical choice at the time).

This emulator is a project I've been working on (and off) since I had a Mac Plus. It runs on the Mac Plus and above (as do all my projects) and it's an emulator for the Radio Shack PC-2 calculator (originally the Sharp PC-1500). This has long been the calculator of my choice.

On the Mac Plus it runs only slightly slower than the real thing. It emulates a bit of the original calculator's hardware quite well (e.g. the built-in clock chip). It's also machine code compatible with the real thing.

So, it runs BASIC and it is machine code programmable. And next to that it also runs the BASIC extensions (LeoBAS 1 and 2) I programmed for the original machine extending its basic functionality with a number of very useful BASIC commands, a new keyboard routine and a new character set.

Well, why can you not download this program? Well, it contains copies of the original ROM of the Radio Shack PC-2, which is copyrighted material. I could distribute it without the ROMs but it is quite hard to transfer the ROM code from the calculator to a PC.

So, how did I copy the ROM? Well, at the time I had an Apple ][. This Apple ][ I own has a relatively simple keyboard input, a data and a strobe signal was all that's needed to input a key code. The connector of the PC-2 has all kinds of handy signals that could be switched from machine code. Thus I wrote a little program that simply 'typed' the ROM codes to the Apple ][ where I captured them. I then sent them to my Mac by RS232.

The calculator is quite useable in its current form, but I can think of quite a number of improvements. For one, it is not PPC native, but since it runs faster than the original on a Macintosh IIcx already I don't think that's a problem.

If anyone has any ideas how I could legally distribute this piece of software please let me know.

PC-2 Emulator screen-dump

The picture below shows what the emulated PC-2 looks like.

PC-2 PC-2 Preferences

Below is the preferences panel of the current incarnation of my emulator.