Not a good time to visit museums, maybe, and the vintage computer festivals either go virtual or get cancelled. But on the other hand, plenty of time to spend at home and tinker!
I built this 100 MHz 65C02 over the past months, to give my Apple II and various old chess computers a boost:
http://e-basteln.de/computing/65f02/65f02/
Not a good time to visit museums, maybe, and the vintage computer festivals either go virtual or get cancelled. But on the other hand, plenty of time to spend at home and tinker!
I built this 100 MHz 65C02 over the past months, to give my Apple II and various old chess computers a boost:
http://e-basteln.de/computing/65f02/65f02/
WOW!, that is amazing (A 100 MHz 6502 (65C02)). As brucehoult said. It is clever/inventive to use the very fast FPGA ram/stuff, rather than the relatively much slower, external RAM/ROM/stuff.
It will be good, when you have the public release version of the PCB, as it seems a neat and interesting project. That particular FPGA, seems to be relatively affordable/cheap, at something like £15 a time.
Although BGAs can be a pain to put on to PCBs.
The old Chess computers, had interesting (vintage) playing styles. But could take a long time, when set to a high setting, in order to give a somewhat good move. E.g. 2 .. 15 minutes. Call it 5 minutes (assuming 1 MHz 8 bit cpu, such as a 6502, or equivalent).
So, that 100 MHz 65C02, would allow playing with the Chess computer thinking it was set to 10 minutes a move, but it would only take, typically, 6 seconds a move. Allowing investigations, into how old vintage Chess computers, can analyse interesting positions/games, at long (equivalent) time settings, and yet the results would come out very quickly.
As your notes say. You do need some kind of 'Turbo' button, or normal (x1), medium (x10) and full turbo (x100), speed settings. Ideally external, without needing to open the device's case. But I suppose a simple turbo mode on/off, would suffice.
When I said x100 faster, I meant when it was the original 1 MHz 6502 applications/hardware. Such as most Commodore Pets/64's, early home computers, and (presumably) some of the early standalone dedicated Chess computers.
E.g. The KIM1 1 MHz 6502, running Microchess.
http://www.benlo.com/microchess/index.html
E.g. The Commodore Pet, probably does keyboard denouncing in software. So if you speed it up by x100 times, it might cause the keys to bounce (unwanted extra repeat keystrokes, when typing), in a very annoying way.
Because the (guesstimate) 10 msec denounce, would then only be 100 usec in duration, which would probably not be long enough.
Similarly, that (and maybe other) related timing issues, may apply to other computers and things.
this works well in practice. The Apple II runs Apple DOS nicely, and the Woz disk controller and RWTS routine are notorious for relying heavily on software-defined timing! Keyboard polling, speaker beeps, and timing the RC delays on the analog paddle inputs also work.
First used '82 or '83, any of
Z80 proto board (1st ASM coding)
ABC 80
MikroMikko 1
First owned '82 or '83
Commodore Vic-20 (2nd ASM coding)
- brain damaged by BASIC
2. DEC Rainbow 100 (ST412 upgrade)
3. Commodore C-16 (hardly ever used)
- brains partially healed by Pascal
4. Amiga 500 (later heavily upgraded)
- USA high-tech embarco softens
- Xenix was also around
5. Unisys PC
- found a mess called simply C
Around '90 I wondered what I'm gonna do with
VAX 11/750 with RL disks, RM disks, TS11 tape and silky LA120 console.
The machine had a 20A mains plug.
Luckily it wasn't finally my problem.
First used '82 or '83, any of
Z80 proto board (1st ASM coding)
ABC 80
MikroMikko 1
First owned '82 or '83
Commodore Vic-20 (2nd ASM coding)
- brain damaged by BASIC
2. DEC Rainbow 100 (ST412 upgrade)
3. Commodore C-16 (hardly ever used)
- brains partially healed by Pascal
4. Amiga 500 (later heavily upgraded)
- USA high-tech embarco softens
- Xenix was also around
5. Unisys PC
- found a mess called simply C
Around '90 I wondered what I'm gonna do with
VAX 11/750 with RL disks, RM disks, TS11 tape and silky LA120 console.
The machine had a 20A mains plug.
Luckily it wasn't finally my problem.
That's a nice lot of interesting computers, to learn from. But I'm not sure I'd fully agree with your opinions, on the various programming languages.
Pascal is nice, we seem to agree!
The old/original C, (in my experience), was marred in the early days, by rather/very buggy and arguably poor quality C compilers, of the time. But it could of been, that I didn't have access to, or obtain, the best C compilers, available, all those years ago.
Some people, seem to dislike Basic, but I think it is quite a good language, within limits, as regards the original/old versions of Basic.
E.g. To write a quick/short program in, to do some useful things with. It just seems quicker and easier, than some of the other languages.
But as the program, becomes bigger and more complicated, the short comings (at least of older Basic dialects), seems to become an increasing hindrance. I.e. not so good (Basic), for bigger and/or more complicated programs.
Depend which variety. I used a fair number of derivatives and the only one that stuck was BBC BASIC on ARM. That was pretty good.
...
2. DEC Rainbow 100 (ST412 upgrade)
...
My very first wouldnt really count as a computer, an intel 4004 based on a practical electronics (practical wireless?) article. Then came a homebrew switch-&-leds SC/MP, then my mainstay for many years, a Nascom-1 built from a kit. It was expanded to the point it was unreliable but with ZEAP assembler and MS Basic both in ROM it was a great development machine. It helped me persuade work to buy a Nascom-2 which was perfectly reliable apart from one day when a tantalum suddenly burnt like a match-head, it had been reversed since its build.
Eventually I got fed up with my own Nascoms problems and bought an Eaca Genie which was great for a few years using ZEN assembler. Next was a CP/M box, the Micronix MX800 which was a badged Ferguson Bigboard and took me to the PC era and an Opus XT-Turbo (8Mhz!). The rest is of no real interest to a retrobate, except to say that the story has gone full circle back to CP/M Z80s
Cheers
Phil