Zengrange Pac

I acquired an HP-41 pac called Zengrange. Does anybody have any ideas as to what it does?


'Zengrange' is the name of the company.
What else is stated on the pac?


Is this an EPROM module? (can you see a quartz window to erase the chip in one side of the module?). My ZEPROM module simply says 'Zengrange' on it.
If it is an EPROM module, then it could contain anything -- these EPROMs were intended to store custom software. Does it show up in CAT 2, and if so, what's the module title?


Cat 2 gives FLT TEST. There are a lot of programs after that. The next few: FLT 1A, Y HAT, f>c, TS, C>F, K>C, FT>M, NI>NIRT and so on... The module has a paper glued on top,it saying #1 with the date 10-12-88 and nothing on the bottom.

There is no quarts window on the side of the pac. Looks identical to any HP pac. When I XEQ FLT TEST, I get a non-existant error message.


If you tried to execute name of the ROM, that might be why it is saying "nonexistant". Try entering 100 and then XEQ C>F, see if you don't get 212. Otherwise "nonexistant" probably means it needs another pack to be present. You could try to load the programs into main memory and then examine them in Program mode, look for statements labeled "XROM xxyy", you can figure out from these what ROM they are trying to use.

The quartz window Tony is talking about might be under the paper label.

Some of those functions sound like temperature conversion, and then you have "ft>m", feet to meters. Maybe something to do with refrigeration?


Sounds to me like it deals with aviation. Some of the apreviations are familiar to me. Like FLT means Flight, HAT might be Hight above Threshold, f<c Fahrenheit to Celsius conversion, TS True Speed and so on. I think that Ellis is on the right way. The modul it self I unfortunaltely don't know but as I have seen Tony is on the Re:-List that's a good start! He helpt me as well a year ago with very good advices. Greetings from Switzerland Stephan.



if you want to burn/load your Zeprom with your own software application or some helpfully rom-image files, I can help you.

Best wishes from Germany - Christoph Klug

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