The Sinclair QL Forum

Dave wrote:

Peter wrote:Since the original speed 68008 allows a high degree of compatibility for games: Are you sure it is a good idea to abandon QDOS altogether? Wouldn't it be better to add sort of a "memory limiter" option?

It requires Minerva to support the 4MB. There is a JS 4MB ROM, but we haven't tested it. If it works, that will be an option also.

Sorry for not being precise. I meant a hardware feature that would optionally limit the amount of available RAM, so normal QDOS ROMs could still run.

Your new card is for people who want to stay with standard 68008 speed. A major reason for this is the possibility to run games (and then QDOS is the more compatible option).

For example: I keep one of my QL still with 68008 and QDOS. Your card would be the finer memory upgrade, but 4 MB is overkill for me on such a slow machine. RAM test would be a pain, and everything else which actually uses 4MB, also. An optional limit at $C0000 would solve this.

In my excitement I misread the original post - I thought it had a 68000 level processor. Is that something you are considering for a later version, or would that be too much of a design shift?

Peter wrote: Your new card is for people who want to stay with standard 68008 speed [...] RAM test would be a pain

If the information I found in the Internet are correct, actually 68008FN10 is faster than 68008 (about 40% faster). Of course nothing similar to a (S)Goldcard. Anyyway, I have no idea of the time will take a RAM test...

Cristian wrote:

Peter wrote: Your new card is for people who want to stay with standard 68008 speed [...] RAM test would be a pain

If the information I found in the Internet are correct, actually 68008FN10 is faster than 68008 (about 40% faster). Of course nothing similar to a (S)Goldcard. Anyyway, I have no idea of the time will take a RAM test...

Only if it's clocked faster - the CPU is just a different packaged option - with 2 additional address lines, 3 IPL lines like on the 68000, and the missing bus arbitration signal - also as per the 68000. It's still 8 bit data bus, and at the same clock frequency is identical in performance to the original 68008 in the QL

Cristian wrote:If the information I found in the Internet are correct, actually 68008FN10 is faster than 68008 (about 40% faster).

No idea what you are referring to. The Motorola datasheet provides same cycles for L, P and FN Suffix.

The 10 MHz version could be clocked higher, but I don't think Dave does that. It would mean that network and microdrives timings get out of range.

Peter wrote: No idea what you are referring to.

The following website. They wrote "10 MHz".
http://www.cpu-world.com/CPUs/68008/Mot ... 8FN10.html

Pr0f wrote: Only if it's clocked faster

Oh, OK. I didn't know. Thanks

For a definitive reply:

We run the 68008FN10 at the QL's 7.5MHz. The 68008FN10 uses the exact dame die as the 68008P8, but in a different package, so it has the same Instructions Per Clock (IPC) and will have the exact same performance as the internal CPU. That said, the internal memory is quite slow, and mirroring tricks should give us a typical 17% speed improvement - more depending on where in RAM your code is running and the amount of reads from internal IO and to a lesser extent screen memory because that is less likely.

The possibility exists to run the CPU at 11MHz, but we haven't implemented it.

Yes, after this we do hope to produce a MUCH faster and more capable board. It would likely be based on the 68EC030 and a modern 5v tolerant FPGA.

Hi Dave,

A question regarding the memory mirroring, does this mirror the complete QL memory map or does it behave like the Gold Card?

The expansion looks great, I really like MInerva and doing without Multi-tasking Basic is some what limiting.

Please put me down for one please.

Dave wrote:Yes, after this we do hope to produce a MUCH faster and more capable board. It would likely be based on the 68EC030 and a modern 5v tolerant FPGA.

A modern 5V tolerant FPGA would be fantastic for QL purposes. Any hint which FPGA family you mean?