The future of computer chess

[smatovic]

[...]
How much can YOU do with today’s algorithms??

I tried to write an 6502 program in C via CC65 compiler for the Atari 800 XE, it performed horrible NPS wise.

But I agree with syzygy and Chris, if someone skilled would give it a real try, to backport for example PeSTO to 6502 with 64KB, it would outperform all the classics, if not simply by evaluation and selective search being tuned.

We definitely do have better software now, more advanced eval, more advanced selective search, but it would be a challenge to backport all that onto limited hardware.

The hardware<->software progress is intertwined, co-evolution, you can not separate the one from the other.

--
Srdja

[syzygy]

[...]
How much can YOU do with today’s algorithms??

I tried to write an 6502 program in C via CC65 compiler for the Atari 800 XE, performed horrible NPS wise.

There is now llvm-mos, which you could give a try:
https://llvm-mos.org/
https://github.com/llvm-mos/llvm-mos-sdk
https://godbolt.org/z/c11Th3oMW

[smatovic]

[...]

Thanks, but I lost the source code of Zeta Vintage, would need to rewrite from scratch, as you mentioned, would be an interesting, fun, project, what can be backported what not, but I lack the time atm for such an endeavour.

--
Srdja

[syzygy]

[...]
How much can YOU do with today’s algorithms??

I tried to write an 6502 program in C via CC65 compiler for the Atari 800 XE, performed horrible NPS wise.

There is now llvm-mos, which you could give a try:
https://llvm-mos.org/
https://github.com/llvm-mos/llvm-mos-sdk
https://godbolt.org/z/c11Th3oMW

The godbolt.org link let's you click "click here to emulate" to let an emulated C64 run a compiled C program that calculates the first 100 digits of pi.

To port a chess engine to the 6502, it would probably be necessary to convert the recursive search into an iterative search. llvm-mos deals with the very limited stack size of the 6502 by analyzing program flow and allocating local variables on the heap when there is no recursion. If there is recursion, it will have to emulate a stack, which is very slow.

[syzygy]

[...]

Thanks, but I lost the source code of Zeta Vintage, would need to rewrite from scratch, as you mentioned, would be an interesting, fun, project, what can be backported what not, but I lack the time atm for such an endeavour.

But anyone interested could give it a try.

The main problem that I see is that nobody will want to operate two emulated C64s and forward the moves between them. This would have to be automated somehow, but that seems tricky.

[Rebel]

1950 ELO Ed Schroeder was able to create out of the 6502 5 mhz 8 bit cpu 64/8 kb rom/ram.

How much can YOU do with today’s algorithms??

100 elo would be doable with nowadays knowledge, search based, I think.

What was not invented in those days :

1. reductions
2. LMR
3. Futility pruning
4. Null move

Should be enough for 100 elo.

What can't :

5. Hash tables with only 8Kb ram, maybe a tiny one for the first 3 plies only.

All in all not much elo progression.

BECAUSE, the real strength of : 1. reductions, 2. LMR, 3. Futility pruning, 4. Null move, 5. Hash tables etc. comes from deeper depths (thus computer speed) and doing only 500-600 nodes per second on 5Hmz is an obstacle for progress.

[Uri Blass]

True.
But at least two 8 bit pioneers (ed Schroeder and Chris W.) demonstrated on todays hardware/ressources
that they are capable to create strong competitive and even interesting playing engines in todays technics.

Would the younger generations of programmers be capable to beat ed schroeders 8 bit 6502 computers if they would use similar ressources ? I highly doubt that.

Take a look here:

http://ssdf.bosjo.net/long.txt

354 Mephisto Nigel Short 6502 5 MHz 1950 ELO

This is a dedicated unit of ed schroeder using 5 mhz cpu 8 bit 6502.
https://www.schach-computer.info/wiki/i ... igel_Short


379 Novag Super Expert C 6502 6 MHz Sel 5 1868 ELO
Dave Kittingers strongest 8 bit 6502 engine
https://www.schach-computer.info/wiki/i ... r_Expert_C

393 Mephisto Modena 6502 4 MHz 1805 ELO
Frans Morsch strongest 8 bit 6502 engine.
https://www.schach-computer.info/wiki/i ... sto_Modena

399 Saitek Turboking II 6502 5 MHz 1777 ELO
Julio Kaplan’s strongest 8 bit unit.
https://www.schach-computer.info/wiki/i ... bo_King_II


400 Conchess Plymate Victoria 6502 5.5 MHz 1776 ELO

Ulf Rathsmanns strongest 8bit

https://www.schach-computer.info/wiki/i ... e_Victoria

404 Fidelity Par Excellence 6502 5 MHz 1745 ELO
Spracklens strongest 8 bit unit.
https://www.schach-computer.info/wiki/i ... Excellence

So where are today’s programmers if they had the ressources of the past ????

Choose assembler, c++ , c, pascal or whatever compiler.
But use the hardware ed schroeder made the most ELO out of 5 mhz.

If you would ask me to tell about ed schroeder, i would begin with showing you a bronze monument.
How good we still can ask him about those days.

1950 ELO Ed Schroeder was able to create out of the 6502 5 mhz 8 bit cpu 64/8 kb rom/ram.

How much can YOU do with today’s algorithms??

I guess that you can add at least 200 elo for Mephisto Nigel Short 6502 5 MHZ on the same hardware thanks to the knowledge we have today but somebody will need to pay for it because programmers are not going to work for something nobody is going to use unless you give them enough money.

The question is how much money do you offer for it.
I guess you need to pay at least the same money that Ed earned from Mephisto Nigel Short 6502 5 MHZ that was a commercial program.

[smatovic]

[...]

Thanks, but I lost the source code of Zeta Vintage, would need to rewrite from scratch, as you mentioned, would be an interesting, fun, project, what can be backported what not, but I lack the time atm for such an endeavour.

But anyone interested could give it a try.

The main problem that I see is that nobody will want to operate two emulated C64s and forward the moves between them. This would have to be automated somehow, but that seems tricky.

IIRC HGM solved this in his Usurpator running in an 6502 emulator:

https://www.chessprogramming.org/Usurpator
https://computerchess.org.uk/ccrl/404/c ... urpator_II

I am not into the details.

--
Srdja

[Uri Blass]

1950 ELO Ed Schroeder was able to create out of the 6502 5 mhz 8 bit cpu 64/8 kb rom/ram.

How much can YOU do with today’s algorithms??

100 elo would be doable with nowadays knowledge, search based, I think.

What was not invented in those days :

1. reductions
2. LMR
3. Futility pruning
4. Null move

Should be enough for 100 elo.

What can't :

5. Hash tables with only 8Kb ram, maybe a tiny one for the first 3 plies only.

All in all not much elo progression.

BECAUSE, the real strength of : 1. reductions, 2. LMR, 3. Futility pruning, 4. Null move, 5. Hash tables etc. comes from deeper depths (thus computer speed) and doing only 500-600 nodes per second on 5Hmz is an obstacle for progress.

I think you forget that part of the strength improvement can be from a better evaluation so I guess at least 200 elo improvement.

[syzygy]

Current hardware would mean 1 cpu since the older chess engines cannot run more then one core.
In a uniform platform tournament, so same hardware, one can try to find out.

I overlooked your reply.
Yes, single core Fruit 2.1 vs single core Stockfish, last release.
Fruit will be crushed.
Do you doubt this?