Simple Dragon Interface ...

[tjewell]

Hi all. I'm trying to build a simple interface between my PC and my old 32. I'm trying to keep this simple and low-tech, so my first design used an Arduino (overkill perhaps) to interface into the joystick port, which I could then read data from (using X & Y as on/off and fire as a 'latch' for 2bit comms!). The one directional nature of this was fine for my initial ideas - using the Dragon to show email alerts or tweets or something.

However, now I've seen the Google Command Line (http://code.google.com/p/googlecl/) I'm starting to have more ambitious ideas, and I'd like to have some sort of 2-way comms. So what are my options? I presume the parallel port is 2 directional - this site (http://www.onastick.clara.co.uk/pcs_parallel.htm) suggests it is, but I didn't like the idea of modifying my old machine. I could use the tape interface, but I've never used that at a low level (is it easy? I guess I could find the rom routines and have a rummage, and produce something on the PC that makes tones ...). Or I could just buy a 64 and use the serial interface, but I'd rather the challenge of doing it on my old 32.

Any ideas?

[dragondata]

Although this might not be an option for yourself, in the past I used the serial port (on a Dragon 64) for comms to a PC. Many years ago I wrote a simple interface into DOS forthe PC so you could do directory listings, change directory etc. from the Dragon, the idea was to use the PC as fileserver but I never got it to that stage.

p.s. I no longer have anything left from that project.

[prime]

I believe that the signals from the PIA that are used on the CoCo by it's serial port are available on the paralell port of the Dragon. So it may be possible with suitable level converters e.g. MAX232, to communicate this way be porting the CoCo drivewire software to the Dragon.

Cheers.

Phill.

[tjewell]

Thanks Phill, that'll give me something to research. I guess first steps are to find a cable that fits that I can then break out, a description of what's on each pin (easy enough) and some pointers as to where they might be memory mapped. This document seems to answer all my questions - http://www.onastick.clara.co.uk/sys4.htm. I guess if I'm looking for a hack, I could use the printer port for output and continue to use my joystick method for input. Ah well, it'll give me something to do with these long summer evenings ...

Any ideas about the cable, anyone?

Thanks all!

Tony.