|Re: HP82104A Cardreader-"G" ROM Info|
Message #3 Posted by Dan Grelinger on 10 May 1999, 5:08 p.m.,
in response to message #1 by Peter Ohanessian
First, to check the ROM version, insert it into an HP-41, and execute catalog 2. You will see something like "CRD RDR 1G". If you have an HP-41CX, only the ROM headers will display, so this will come up after only a few entries, depending on how many other ports have something in them. If you have the HP-41C or CV, the program and function names will be displayed as well, so do this with nothing else in the other 3 ports, and you will see the card reader header first thing.
Secondly, there were several ROM versions, and the last one, version "1G", fixed a significant bug for users of the card reader and extended memory. The Card Reader "VERIFY" command would write over data stored in an extended memory module (HP82181A) that was in port 2. This could ruin a file, or the directory itself, obviously disastrous if the memory was being used.