ECS to Arduino?

[JohnPCAE]

I've been trying to learn a little bit about the Arduino and I had a weird thought...could an Arduino be interfaced to the ECS ports (tape in/out, aux, controller) to enhance what's possible? I'm wondering if this would allow for an easy way to add things like savegame support, extra memory storage, or other ideas (the Arduino can interface to a lot of different things).

 

It might mean having to completely reverse-engineer the ECS E0/E1/E2 UART bit settings to squeeze out its full potential. I wonder if some of the bits control the parity, number of stop bits, baud rate, or number of data bits.

 

Another possibility might be using the ECS 26-pin expansion port, though not all of them have the connector for it (mine doesn't, for instance). mouser.com seems to have a connector that might be a good replacement, though, so this might not be all that big a hurdle.

 

Anyway, just some idle thoughts I had when not working on other projects...

 

John

[intvnut]

Perhaps easier and more worthwhile would be to interface to the two 8-bit I/O ports that the keyboard connects to, and act as a pass through/emulation for the keyboard as well. Use a special handshake from the Intellivision to indicate you want to talk to the Arduino directly, otherwise have the Arduino scan the keyboard in the background and reply to keyboard scan requests as if it were the keyboard.

 

That would also allow you to build a dongle that keeps both the ECS keyboard and Synth connected at the same time, using a simple switch to switch between them, and opens the possibility of adapting a PS/2 or USB keyboard to the ECS, in addition to whatever other magic you want to throw in there.

 

My "ECScable" work from several years ago shows that the PSG I/O ports can be pretty effective for I/O. Just set the direction bits in bits 7:6 of location $F8, and you can do I/O through $FE and $FF.

[intvnut]

Oh, and FWIW, I believe that 26-bit I/O port is just exposing the Intellivision's regular bus, maybe with a few control signals decoded. I'm not sure it's a great port for interfacing a slow MCU to. You'd need something fast enough to emulate the full bus control protocol. I don't know how fast the Arduino is, but a 40MIPS PIC24 is just fast enough.