Harvey B. Herman, Associate Editor
The hardware reviewed here will be of interest to a select group of COMPUTE! readers. If you own a VIC and have the need to "burn EPROMs," you should consider this cartridge. On the other hand, if you are completely befuddled by the previous sentence, go to the next article; save $200.
I was excited when I received the PROMQUEEN for review, as it was just what I needed. Several pieces of computer-related equipment which I use daily contain EPROMs (Erasable Programmable Read Only Memory chips). What would I do if one failed and I had no way to replace it? The PROMQUEEN promised to solve this potential problem, even for one like myself, who had never programmed an EPROM before.
It is misleading to think of the PROMQUEEN exclusively as hardware. What is visible, of course, is a cartridge (hardware), which plugs into the memory expansion port of the VIC. But it also comes with essential software (actually firmware on EPROM) without which the hardware would be useless. A 25-page instruction manual is included as well.
The major function of this product is to allow the user to conveniently burn EPROMs. That is, data is to be stored into an erased EPROM so that it will be there the next day even after power has been turned off. This data can be copied from a previously programmed EPROM or typed in from scratch using the monitor program provided.
I was a little apprehensive on my maiden EPROM burning session. First, an EPROM had to be erased. No problem here. I used a shortwave ultraviolet mineral lamp (2537 A wavelength). The shortest erase time I tried was 40 minutes. If you don't have one of these lying around, there are several advertised units which should be satisfactory.
Next, I attempted a copy of the EPROM Hexkit program which comes with the PROMQUEEN. The instructions were somewhat confusing. It was not immediately clear that there is both RAM and ROM memory in the package and that you have the option of moving these around by switches. The ROM memory is only there if an EPROM is plugged into the external socket. However, I was using a preliminary manual. The manufacturer promises that an improved manual will be available shortly.
The burning of an EPROM is actually easy once you know what you are doing. The procedure is:
- Insert the Hexkit EPROM in the zero insertion force socket (ZIF).
- Set the switches correctly.
- Transfer the program to the VIC RAM with a SYS call.
- Insert the EPROM to be copied.
- Transfer the EPROM data to the PROMQUEEN RAM using the transfer function of Hexkit.
- Insert the erased EPROM (2716, 2732 or 2732A – a 2532 will not work).
- Use the burn function of Hexkit. The software first checks for a properly erased EPROM and later verifies the burn. After several false starts, I had successfully burned my first EPROM.
I have not described all of the features of the PROMQUEEN. The Hexkit program has many other features in addition to the burn function. It also uses color effectively: red screen when burning, for example. The hardware has lights (LEDs) which minimize the chance of error. It can also be used to emulate a ROM when working with other computers.
As with most equipment, I can cite good and bad features. The cartridge is well-constructed and easy to use once you know how. However, the version I tested included confusing directions and it is priced at more than twice what a similar system for the PET goes for. Nevertheless, if you need an EPROM burner and already own a VIC, this could be the best way to get one.
Gloucester Computer Bus Co.
6 Brooks Road
Gloucester, MA 01930