Any idea if there are efforts afoot to reverse engineer some of the more sought after QL expansions?
I'm thinking Trump cards specifically. I haven't seen any circuit diagrams but they must be reasonably simple, given the technology of the time. I'd like to see something like the UltraSatan which is a hard drive emulator for Atari STs with memory expansion, but I'd settle for a straight Trump Card emulation. I'm not sure how economically viable it would be, but think of the service done to the community (keeping the QL going)!
Everyone knows how unreliable microdrives are getting with age. Even a reconditioned one (new pad, retensioned pad spring) which I've used no more than ten times is showing signs of wear (the pad is disintegrating). Isn't it time for a simple slot in card reader (with additional memory)?
So, has anyone tried to do this, or is trying.. Or are we doomed to carry on chasing after these rare (and costly) 3rd party add ons?
Reverse engineering rare hardware
Re: Reverse engineering rare hardware
I have been steadily working on this. Currently I have a SRAM memory expansion prototype, working floppy expansion based on the Sandy SuperQBoard, and the big one is a complete QL replacement board with 24 MHz 68020, on-board floppy, IDE and tons of RAM.
These will take a while, and nothing's guaranteed, but they're the best efforts going on right now.
These will take a while, and nothing's guaranteed, but they're the best efforts going on right now.
Re: Reverse engineering rare hardware
The replacement board is quite an achievement, but then it ceases to be a QL.
Re: Reverse engineering rare hardware
I think it ceases to be a QL when it ceases to run QL Pawn 
More seriously though... In a real sense the board I'm playing with is a real QL. It's simply a QL re-implemented with the exact same custom logic and a mostly-the-same CPU, with the commonest expansions inbuilt. It doesn't make sense to design individual cards for these, alas, unless at least 50 or 100 can be sold. Is a SGC/Aurora combo not a QL?
Do you think there's a market for 50 of anything these days? If you make 50 or 100, you'll sell three or four quickly, but it will take many years to sell the remainder.
More seriously though... In a real sense the board I'm playing with is a real QL. It's simply a QL re-implemented with the exact same custom logic and a mostly-the-same CPU, with the commonest expansions inbuilt. It doesn't make sense to design individual cards for these, alas, unless at least 50 or 100 can be sold. Is a SGC/Aurora combo not a QL?
Do you think there's a market for 50 of anything these days? If you make 50 or 100, you'll sell three or four quickly, but it will take many years to sell the remainder.
Re: Reverse engineering rare hardware
Dave, Jon,
I agree with Dave - If it run's QL software, it's a QL. If it even lives in a black box, it's a real QL.
Regarding the size of the "market" for replacement boards - 20, 30 maybe? 50 rather not, but depends on price. I'd definitely be your customer for one of them
Why don't you start a web poll?
Tobias
I agree with Dave - If it run's QL software, it's a QL. If it even lives in a black box, it's a real QL.
Regarding the size of the "market" for replacement boards - 20, 30 maybe? 50 rather not, but depends on price. I'd definitely be your customer for one of them
Why don't you start a web poll?
Tobias
ʎɐqǝ ɯoɹɟ ǝq oʇ ƃuᴉoƃ ʇou sᴉ pɹɐoqʎǝʞ ʇxǝu ʎɯ 'ɹɐǝp ɥO
Re: Reverse engineering rare hardware
Dave
Don't get me wrong, you know I am interested in expanding my QL, and I am happy to consider any of your designs. At the moment it seems my shopping list comprises a Trump card, floppy drive and Minerva ROM.
I have no idea why I like playing with it, but I do. That said, every time I use it a microdrive cartridge jams on me. So getting an alternative storage medium is getting urgent.. I'm running out
They seem so expensive though...!
Don't get me wrong, you know I am interested in expanding my QL, and I am happy to consider any of your designs. At the moment it seems my shopping list comprises a Trump card, floppy drive and Minerva ROM.
I have no idea why I like playing with it, but I do. That said, every time I use it a microdrive cartridge jams on me. So getting an alternative storage medium is getting urgent.. I'm running out
They seem so expensive though...!
Re: Reverse engineering rare hardware
I'm confident a short run of low cost floppy interfaces with 512K of RAM will surface in the next few months from one source or another - there is sufficient demand.
Re: Reverse engineering rare hardware
The trumpcard uses a PAL chip (at least the Trumpcard II which uses 256k x 4 RAM chips, so only 6 of them instead of the original 24!). However, you can do better today. The Trumpcard, for instance, uses a counter to generate a refresh address for the RAM, whereas even the 256k x 4 RAMs implement one internally. Also, today 1024k x 4 RAMs are available as well as (actually more commonly) 4096k x 4, so only two are required to cover the entire available memory map and more, which means you actually implement a 'large RAM' and then not use areas of it that are addresses used by the QL itself, but it also makes it possible to use things like video RAM shadowing to get a bit more speed out of the old box.
If static RAM is used, all of this is almost trivial, and in fact it may well be the cheapest to make, as only a single RAM chip is required (there are several types of 1M x 8 SRAM chips around, 5V operated), and a decoder implemented in a small CPLD such as a GAL. It could easily implement all the RAM expansion functions of a Trumpcard including advanced options the Trumpcard did not have such as memory shadowing, and it would take a single free pin and a floppy disc controller (WDC1772) plus two TTL chips to make it a full trumpcard. It would also use a fraction of the power used by a Trumpcard.
If static RAM is used, all of this is almost trivial, and in fact it may well be the cheapest to make, as only a single RAM chip is required (there are several types of 1M x 8 SRAM chips around, 5V operated), and a decoder implemented in a small CPLD such as a GAL. It could easily implement all the RAM expansion functions of a Trumpcard including advanced options the Trumpcard did not have such as memory shadowing, and it would take a single free pin and a floppy disc controller (WDC1772) plus two TTL chips to make it a full trumpcard. It would also use a fraction of the power used by a Trumpcard.
Re: Reverse engineering rare hardware
Why not make it two 512k SRAM chips and make it real snazzy - the extra cost is negligible (a WDC1772 costs more second hand than both SRAM chips...)Dave wrote:I'm confident a short run of low cost floppy interfaces with 512K of RAM will surface in the next few months from one source or another - there is sufficient demand.
