ZX-24 suitable for this project?

[Just Another Joe]

Hello. It's been many years since I've done development with microprocessors, and some years also since I've done much programming, so I'm not up to date with the latest offerings. But, I'm wondering whether a ZX-24/ZX24a would be suitable for the following small project:

The ZX-24 would act as a communcations manager, requiring four serial ports. The primary (hardware) port would connect to a PC for programming/downloads/etc. Of the other three (software) ports, the first would connect to the primary device, itself a microcontroller, at 9600 baud. The second and third would each connect to a communcation device; one at 4800 baud, the other not yet determined, but likely 9600 baud. If that is too much load, I would be willing to add additional UARTs as required.

The primary device would send/receive traffic from the communications devices. Since each of the three devices has an entirely different protocol, the ZX-24 would act as a translator, possibly by use of look-up tables. Traffic would range from light, up to nearly constant. I would anticipate having the ZX-24 run in multi-tasking mode. From the PC, the ZX-24 could also be placed into a pass-through mode to any other device, to allow the device to be programmed from the PC.

Does this sound like a reasonable application for this processor?

[stevech]

I'll guess that this will work well. If the the software UARTs are all at full capacity (constant data) it might be a challenge, not sure.

[Just Another Joe]

Thanks, Steve.

There doesn't seem to be a ZX-24 development kit. Since it is pin-compatible with the BX24, does one buy the BX24 development kit in order to develop for the ZX-24a?

[stevech]

The compiler is a free download.
I suppose you could use any BX-24 protoboard.
Or
simply plug the ZX24 into a solderless breadboard and plug in a PCB mount RS232 female DB9 - no soldering. I did that.
Or
buy on ebay from Peter Anderson his really low cost ZX/BX PC board and parts kit. I did that too.

Pretty easy.

[dkinzer]

There doesn't seem to be a ZX-24 development kit.

Because the ZX-24 can be used in many of the existing dev boards there hasn't been much motivation to produce yet another one. We usually run ours on a solderless breadboard. The advantage of doing that is that it provides additional space for external circuits to be constructed. The solderless breadboards may be obtained from a variety of sources. If you live near a Fry's Electronics, you'll probably find them in their parts section. We've purchased several from JDR.

We have also run the ZX-24 and ZX-24a in the Parallax Serial BOE; I expect that it would also work in the USB BOE. We have also run them in the the NetMedia BXDS-1 and Prof. Anderson's BX24 Protoboard. In general, nearly any prototyping board that is designed for the BasicStamp II or the BX-24 will be suitable for the ZX-24.

[Just Another Joe]

Thanks Steve and Don for that good information. I really like Peter Anderson's offerings, and will likely go with his low-cost BX24 prototyping board.

Regarding breadboards, I note that Peter highly recommends the Jameco JE25 Solderless Breadboard, calling it "the best board less then $100" and saying it doesn't corrode or become loose and intermittent over time, as others can do (see link).

[dkinzer]

[Prof. Anderson recommends] the Jameco JE25 Solderless Breadboard[...]

I've not had my hands on this particular one but it looks like a private-label version of the EIC-104 manufactured in Taiwan by E-Call Enterprise Co. I do have one of those and have been pleased with it. My only objection is that I prefer a single buss bar between the two sections (like the EIC-104-1) rather than the double buss bar but that's not a significant factor. If you anticipate larger projects, you might consider the EIC-106 or EIC-108.

I've found some of the EIC breadboards at good prices at Computronics Technology in Texas.