The Sinclair QL Forum

(I think there are Amiga folks that have the same concerns from comments I've read).

There has been a backlash against the Vampire FPGA for some of the same reasons too, its just not an Amiga is the common argument!

mk79 wrote:

Peter wrote:Don't have the time to watch the full video, but two things seem odd at first glance:

1. They mention "prices as low as about 13 €" while the PLD alone (no PCB, no assembly, no small stuff) costs 21 € and has delivery time January 2022. China fakes?

No fake, they use JLCPCB for assembly and there the chip costs 4.80€, but is currently out of stock. I use them for basically all my prototypes and they assembly for as little as 6€, but you have to wait until things are in stock, which is a bit annoying.

Marcel

But where does the chip cost 4.80€? When authorized distributors call four times more, it usually has a reason.

Peter wrote:But where does the chip cost 4.80€? When authorized distributors call four times more, it usually has a reason.

https://jlcpcb.com/parts/componentSearc ... M570T100C5
https://lcsc.com/products/CPLD-FPGA_111 ... M570T100C5
JLPCB gets its parts form LCSC, they are sister companies. They have a fairly good reputation.
Why is everything so much cheaper in China? Who knows, maybe scale of economics. Maybe because they are in the center of where this stuff is actually produced most of the time anyway. Maybe they get the remaining parts of larger productions cheaply. Unlike very cheap parts from AliExpress they are definitely new and unused. And given the complexity of the chips I doubt that they are counterfeit.

bwinkel67 wrote:From what I've seen the bootup is relatively fast (they seem to use a very lite installation for the Pi)

Not very light, it is the standard distro without GUI. I use that also.

bwinkel67 wrote:and powering down is just shutting the machine off.

Which can cause data loss, and seems criticised in the Amiga scene.

bwinkel67 wrote:I think the issues are similar to what a GoldCard or Super GoldCard encounter, no?

Not too much. The GC/SGC are designed to use the full bandwidth of the 68008 bus. Both have CPUs with well defined instruction timings. They are "instant-on" and need no shutdown.

Note that a lot of firmware development was done by Mr. Tebby himself, to get these true 68000 / 68020 systems to work relatively well with the QL. And it is not that you could just re-use that firmware with slight modifications - the approach is different and the amount of work is not smaller.

mk79 wrote:JLPCB gets its parts form LCSC, they are sister companies. They have a fairly good reputation.

Okay so Chinese. That explains it. I never purchase ICs from such sources.
Out of curiosity, I looked up some of those PLD in stock at an authorized distributor. For stunning 41.08 € - more than the whole Raspi. Else wait until January 2022.

Peter wrote:Which can cause data loss, and seems criticised in the Amiga scene.

This issue came up on the Discord server and Claude himself said there was no issue with power down the Amiga and no data loss had been reported in tests or by any users. The only recommendation is that if you have a hard drive to let it spin down (an Amiga thing though, not a PiStorm thing).

Peter wrote:

Peter wrote:Which can cause data loss, and seems criticised in the Amiga scene.

I'll have to re-watch the videos but it seemed no longer than standard. Also, you may gain time if you avoid the memory boot check, which takes longer for more memory so it may be a wash.

Peter wrote:Not too much. The GC/SGC are designed to use the full bandwidth of the 68008 bus. Both have CPUs with well defined instruction timings. They are "instant-on" and need no shutdown.

Note that a lot of firmware development was done by Mr. Tebby himself, to get these true 68000 / 68020 systems to work relatively well with the QL. And it is not that you could just re-use that firmware with slight modifications - the approach is different and the amount of work is not smaller.

Actually the only problem is getting the timing of the MDV and NET routines right, the rest is pretty trivial. A 68000 based solution works for the most parts even without a single patch.

But believe it or not, I do agree with you that this whole thing still feels strange. In the end it would probably just use the keyboard and nothing else, with the rest being emulation. Even I am not sure I agree with that

mk79 wrote: But believe it or not, I do agree with you that this whole thing still feels strange. In the end it would probably just use the keyboard and nothing else, with the rest being emulation. Even I am not sure I agree with that

On an Amiga that makes a lot of use of its many custom chips, the PiStorm actually makes a lot of sense to me.

For a much more straightforward "standard" hardware computer like the QL, not so much.

mk79 wrote:Actually the only problem is getting the timing of the MDV and NET routines right, the rest is pretty trivial. A 68000 based solution works for the most parts even without a single patch.

But believe it or not, I do agree with you that this whole thing still feels strange. In the end it would probably just use the keyboard and nothing else, with the rest being emulation. Even I am not sure I agree with that

Yeah, if you can only integrate the keyboard it would be useless. I was really seeing this more as an inexpensive replacement for SGC that could be tweaked to run a bit faster if wanted. But if all it is is a Pi emulator that completely takes over then it's pointless. On the Amiga there are options of bypassing the internal video and audio and using the Pi so in that case they'd have the same issue. For the QL, if you can tie in the ROM port, serial ports, net port, and MDV, that would be pretty cool...I guess that would be the challenge to get a PiStorm for the QL.

I suppose the other route would be an inexpensive expansion that emulated the 68008 at speed through say a Pi Zero W but gave you more memory, sd hard drive, wifi and maybe HDMI out (or some combination of that). If you could get all that on a BBQL for $25 that might make it worthwhile. And if there could be an option to speed boost it by a small factor (x2 maybe) could be a cool addition.

mk79 wrote:

Peter wrote:Is it done by RPi GPIO oder did they at least use the SMI bus?

There doesn't appear to be any schematic, but according to the sources it's a simple 16-bit GPIO interface.

Probably wrong, according to a post on English Amiga board" http://eab.abime.net/showthread.php?t=104462 PiStorm at least uses the SMI bus. That would make the 68000 bus interface significantly better. But overall, it's still a Linux box in most aspects.

Slightly more appealing to me would be the Buffee solution https://eab.abime.net/showthread.php?t=105641 which also comes with 68000 socket. That one just provides a fast CPU and memory but does not depend on a fullblown Linux system.