QIMI Working!

[prime]

Hi all,

Just got my QIMI clone working properly, pictures here :

https://www.facebook.com/media/set/?set ... f5a72bc540

The board currently has 2 functions :

1) as a QIMI clone with conversion from PS/2 by an onboard ATMega 8 (AVR).
2) as a replacement for the two roms on the QL with a single 27512, which you can burn the rom of your choice (Minerva in this case).

This is just the prototype proof of concept which is why I used a DIP AVR and a PLCC XX9536XL as that's what I had to hand, have plans for the next version which will use surface mount chips for the AVR & CPLD.

As for why I decided to "re-invent the wheel" when plans for a clone already existed, well for one I didn't become aware of the other clone until after I'd built mine and secondly I wanted the dual function which the other board didn't have.

Cheers.

Phill.

[dilwyn]

Very nice, Phill.

Great that variants of QIMI are being made to use PS/2 mouse since the Atari ones are hard to get and expensive now.

[dilwyn]

Just an after-thought: how feasible would it be to make a board like this which included sockets for both a Minerva and a Sinclair ROM alongside the QIMI?

One of my QLs has an old QLEA ROM card which lets me have a Minerva and Sinclair ROM. That QL actually has a QIMI too, but it's pretty clutteredinside.

Obviously, having both would need a switch or jumper to select ROMs, and would need to remain within QL power limits.

[prime]

What would be possibe is using a 32pin eprom / flashrom and controlling the upper address lines with a switch or swotches, to select one of a series of roms....may even be possible to do this in the cpld by poking the location used by the QIMI. In this way the poke would select the rom, and reset the machine.


Cheers

Phill.

[prime]

Hi all,

OK so I tested this idea this evening, made up a 32pin to 28 pin rom adapter, programmed a 39DF010 with Minerva in the bottom 64K, JS in the top, wired up the additional address lines to the CPLD, and the R/W line from the ZX8302 socket.

Made the required changes to the CPLD so that a write to $1BF9E will select the rom bank that becomes active at the next reset.

At power on the latch is 000 so in this case Minerva is selected, but poke 114590,1 and then press reset and JS is active. The design can take up to a 29F040 (or anything with the same pinout) which would allow 8 banks of ROM, so you could have AH, JM, JS, TB, MGx, Minerva in there and 2 free banks.

Note the output bank is only changed by a power on (reset to 0) or by the poke, so stays across subsequent resets.

Now to order some parts for the next version.

Cheers.

Phill.

[1024MAK]

Nice work

Mark

[QLObi]

He Phill,
nice work, but the reason why i tried to make it as small as possible is that i have a QLSD on board which occupy the left EPROM slot and has its own decoding on board. With your current prototyp this place is blocked. There is still an option to move with the QL-SD to the external connector, but it's not at the top place for development at this time.
The orginal intention of my work was a 1:1 replace of the orginal Qimi and by the way to solve the nasty mouse problem.
I am still like to exchange the experince with the Atmel programm with you, due to the fact that some people reported an incompatibility with my adapter for some mices, but nobody was able to give an incompatible mouse to me for further investigation. My sources are published on the german forum, as long as i hadn't translated the whole project to english.
Version 1.03 is emulating a mICE mouse and 1.04 is for an Atari mouse.

Detlef alias QLObi

[prime]

He Phill,
nice work, but the reason why i tried to make it as small as possible is that i have a QLSD on board which occupy the left EPROM slot and has its own decoding on board. With your current prototyp this place is blocked. There is still an option to move with the QL-SD to the external connector, but it's not at the top place for development at this time.

Yep just an initial prototype, a proof of concept, now I have it working i can work on shrinking it, I should now be able to move to using the other ROM socket as the next prototype will use a surface mount CPLD / AVR.

The orginal intention of my work was a 1:1 replace of the orginal Qimi and by the way to solve the nasty mouse problem.
I am still like to exchange the experince with the Atmel programm with you, due to the fact that some people reported an incompatibility with my adapter for some mices, but nobody was able to give an incompatible mouse to me for further investigation. My sources are published on the german forum, as long as i hadn't translated the whole project to english.
Version 1.03 is emulating a mICE mouse and 1.04 is for an Atari mouse.

I'll zip up my source and post it, though it is in C.

Ok AVR source available here :
http://penguin.stats.warwick.ac.uk/~sts ... 1.2.tar.gz

Cheers.

Phill.

[Dave]

I am interested in this. If you're interested in open sourcing or licensing your design when it's finished, please email me off-forum.

[prime]

OK here :

https://www.facebook.com/photo.php?fbid ... =3&theater

Is a picture of the second prototype, this has TQFP chips to allow the board to shrink to just using the ZX8302 and right hand ROM socket. This allows the QL SD to plug into the left.

The board supports either a single 28 pin 27512 Eprom with the rom version of your choice in or a 32 pin flash rom / eprom with up to 8 banks of rom, which are mapped into the lower 64K.

Rom banks are selected by poking the bank number into 114590 thus :

bits 0..2 : bank number 0..7
bit 4 if 0 then the rom ins not mapped into $c000-$ffff (default), if 1 then it is. This allows the cartridge rom to be on the built in rom or on a physical cartridge.

The new rom bank is made available next time that the reset is pressed, this allows for several versions of the rom to be present in the machine and software selectable e.g. Minerva and JM (for example)...even Tyche works as long as you enable the cart rom for it's bank...

Next step is to be to get a small number of professional boards made to further test the design.

Cheers.

Phill.