Review: TechTools UniROM
I've been using a UniROM, from TechTools pretty steadily for about the last few years, and it's been an outstanding product. I've used it to emulate everything from an 8Kx8 EPROM to a 2MBit FLASH, and it's performed nearly flawlessly.
The UniROM is more than a simple EPROM emulator -- it also comes with a program that lets you change view live memory, and change locations on the fly. I haven't used this a great deal, but it can be a powerful debugging aid.
Another unique feature of the UniROM is it's support for a "virtual UART". If you can afford to give up a half-dozen or so bytes of code space, the UniROM will emulate a UART, giving you an extra RS-232 port that you can use for debugging or for a monitor. Again, I haven't used this feature as much as I'd like to, but I almost certainly will at some point; it just has too much potential to ignore.
Another thing that impressed me about TechTools is that when they released an updated version of the UniROM last year, they performed a hardware upgrade for free -- all it cost me was shipping. And the upgrade was more than cosmetic -- the download speed was greatly improved. I can now download a substantial program in just a few seconds.
In addition to the ROM emulator itself, the UniROM comes with both serial (RS-232) and parallel (printer port) cables, the memory viewer/editor program mentioned above, a batchable downloader, and some useful utilities. Documentation is well-done, and support (the little I have needed it) has been solid.
Bottom Line: Highly Recommended!