|HP41 ROM module versions: anyone?|
Message #1 Posted by Vieira, Luiz C. (Brazil) on 19 Nov 2009, 6:30 a.m.
Hi, all HP41 users and addicts! ;-)
Just to add a time reference: do you remember this?
Those of you who deal with ROM images (MLDL, Clonix and related stuff) know that there are different versions for the same application/program set. I am trying to locate and store these different versions with the sole purpose of studying and learning (35YO+ technology and still going!). I have some different versions of some common ROM images and I still need to download a few ones (stored in actual hardware), but there are some 'gaps' in some version sequences I do not know if were filled with actual, commercial versions or if they never left the labs. There is also the OS ROM versions, and based on what I saw, each of the three basic ROM has its own version flag, which leads to another question (coconut related): is there any information regarding compatibility and/or restrictions or these three OS 'packs' (one IC each) can live together in any possible combination?
Because Meindert´s MLDL2000 has room enough to store up to 253 4K-word ROM images (FLASH ROM), I think most of these images may find their place over there at the same time. I checked TOS and found only one version of most available ROM (did not check all of them), but it does not mean it is the only one stored there. I will send an e-mail to TOS webmaster and ask about this.
Most of us here know of one single place where many HP41 ROM modules found shelter, but this particular source is void, no ROM image will be disclosed from there. Anyway, I believe that the ones that were lucky enough being out here are in hands that might be interested on sharing such data base, mostly because it is 35YO and will serve no commercial purpose. As an example, I have a working Extended IO module with a checksum value that does not match, but I also have a ROM image of another Extended IO, same version, with a valid checksum value. Well, it is somehow easy to change the checksum value, but what if the ROM contents are actually faulty? Only with another version or an original blueprint to check for possible errors.
We surely know that the MoHPC is not the place to exchange ROM images because of also very well known reasons, and I (as all of you, I guess) completely agree with Dave´s thoughts about that. Some of the ROM images I have stored here with me were downloaded from actual hardware, but I also happen to have ROM images I downloaded from the www. I took into consideration that if they are publicly available, chances are that they are public. So, if anyone wants to share this sort of information in an off-line fashion, I'd also gladly share the ROM images I have. Please, use the following e-mail address:
lc_vieira (aT) QUANTICA punto Com [dot] br
In time: I had some issues trying to download a card reader ROM image by using a NoVRAM and a MLDL2000 and did not get the results I wanted to. Because of evident physical issues, I used the NoVRAM to capture the card reader ROM image first, then I tried to copy it to a single SRAM block in the MLDL2000, but somehow the card reader image disturbed the HP41 operation. I happen to have 1E ROM version already stored (the one with that interesting bug already mentioned here some years ago), but I want to keep a copy of the 1G version. Anyone wishing to discuss this as well?
Edited: 19 Nov 2009, 6:36 a.m.