|Re: trying to work with Zenrom, Novram and Advantage together|
Message #2 Posted by Vieira, Luiz C. (Brazil) on 22 Jan 2006, 1:48 p.m.,
in response to message #1 by Fulcrum
first, consider that HEPAX emulated by NoVRAM tries to allocate itself in the first, lower-numbered, available page (HEPAX documentation calls these 'blocks' instead of 'pages'). As each page is also switcheable into four banks, HEPAX uses the four banks in the lower available page; as each page addresses up to four banks, 4KBytes each bank, HEPAX is actually a 16KByte-ROM module. It might be good idea to also check how is the NoVRAM RAM addressed.
I am not sure about ZenROM, maybe it goes to the lower page related to the port it is plugged in. And the Advantage occupies two banks in the lower page plus one bank in the upper page of the port it is plugged in.
So, consider that only the NoVRAM is plugged in and you want to know which page is the PPCROM addressed. You can use HEXEDIT and test for each of the known page addresses. If yours is an HP41, plug only the NoVRAM and try this:
[XEQ][ALPHA]HEXEDIT[ALPHA] [ADR:_ _ _ _ ]
If the HEPAX is actually allocated to page #5, you'll see
HEPAX ROMbriefly in the LCD and the input message [ADR:_ _ _ _ ] back to the display. Now you can try other addresses in the range 8000 to F000 so you can find which page is the PPC ROM allocated to. To try another address once you are already navigating in one page, press the back-arrow (correction) key and key another address in. To exit HEXEDIT, press back-arrow key in the [ADR: _ _ _ _ ] display.
Once you key in a valid address, you can navigate with [SST] and [TAN] keys, being [TAN] equivalent to BST. The regular HEXEDIT display is:
[XXXX YYY _ _ _ ]where XXXX is the current address, YYY represents its contents (000 to 3FF) and _ _ _ is the input-cue reminder. If you see nothing but 000 in YYY field as you navigate through the page contents, this means the page is empty, i.e., no modules addressed to it. After finding where is the PPCROM image allocated to, you'll be able to plug the other modules accordingly. My suggestion is: plug the NoVRAM in the lower port (prot #1), locate the PPCROM image, turn the calculator OFF, plug the other modules in, one at a time, locate where are they allocated, and see if there is no conflict. I'd suggest Advantage in port three and ZENROM in port four. This would give port 2 free for HEPAX RAM pages. In any way, Diego is the guy to tell you how it is organized.
I saw that in a halfnut HP41CV, HEPAX in NoVRAM occupies port #5, and in a halfnut HP41CX it goes to port #6 (port #5 in the HP41CX is internally used by X-Functions/Time Module).
Not so much of a help to solve the problem, but I guess it will help you going ahead.
Edited: 22 Jan 2006, 3:18 p.m.