MGf ROM

[RWAP]

A contact in France (too unsure of his language skills to use the forum) contacted me about the MGf ROM.

He thinks that his ROM chips have developed a fault - whilst the 32K ROM Chip (0000 ?) appears on Dilwyn's site - the 16K 8000 ROM is missing (I think this was the same across all versions from memory).

Anyway - does anyone have a spare set of MGf ROMs, or can someone supply an EPROM version on carrier (in place of Minerva) ?

Someone needs to make some new EPROM carriers, as I do often get asked for Minerva ROMs etc and I only have my own (which I sometimes lend out) and a stock of JM ROM chips!

[smsq4ever]

Greetings,

I just read your post and may perhaps help: while I don't seem to have kept a dump of the MGF ROM of my first QL, 30 years ago, I patched the said ROM to be able to use the second screen memory bank of the QL (by simply changing the related and existing QDOS system variable), which allowed for "real time" animations. I called the patched ROM "MGX" and submitted it to QLCF (QL Contact France).

Here it is, attached, with both AZERTY and QWERTY keyboard versions for the second ROM half (IIRC I just copied the JS ROM keyboard table into the MGF ROM table for the QWERTY version).

Enjoy !

[dilwyn]

Thank you, I will make these available through the QL ROMs page on my site.

[smsq4ever]

Note that I don't remember exactly how the second screen was enabled (on boot ? SHIFTed F1/F2 ?... Not sure any more), but all display related QDOS TRAPs #3 were modified to take into account the actual screen address...

So there will be some trial and error to do with those ROMs, but they are otherwise identical to the MGF ROMs (and IIRC, by default they boot with the system variables in the usual place and just one screen).

I also have a toolkit I made that allowed to set the current drawing and display banks and swap them (so that drawing could occur in the background and once done, have the screen bank switched for the display); time permitting, I may exhume the sources and give them away...

[dilwyn]

Note that I don't remember exactly how the second screen was enabled (on boot ? SHIFTed F1/F2 ?... Not sure any more), but all display related QDOS TRAPs #3 were modified to take into account the actual screen address...

Assuming you made the startup keypresses like a Minerva, the Minerva manual says

If all your memory passes its physical, you then have the option of pressing F3 or F4,
which goes through some of the start-up code again in order to enable the second screen
- we couldn't figure out a way of moving the system variables without bringing the system
down around our ears, and leaving them permanently at the second screen location
would confuse the (badly-behaved) software that assumes the old location. F1 and F2
have the original effect of putting you in monitor or TV mode - in combination with
SHIFT the memory is cut to 128K, with CTRL the ROM scanning is omitted for really
badly-behaved software.
After F3 or F4, pressing the screen switch key CTRL-TAB should now give you a
blank screen instead of the pretty coloured dots and things that appear when you screen
switch on a single screen MINERVA.

[smsq4ever]

Assuming you made the startup keypresses like a Minerva

LOL ! The MGX ROM patch was done loooooong before Minerva existed... It was back in 1986, shortly after I bought my first Sinclair QL... So that would be the other way around: Minerva would have done like me !