Collector's Corner : Cosmic / Maestro Stalemate Bug (Steve?)

[JonP01]

Hi all,

I used to own a Saitek Cosmic machine a few years back but decided to sell it owing to a bug that often resulted in stalemate when the machine was in an overwhelmingly won position. The bug specifically causes Cosmic / Maestro to play a move resulting in immediate stalemate when the alternative is a forced mate (usually in 2 moves, so very easy to find).

In a recent discussion about HIARCS, I noted that this PC engine (and others) will sometimes do a similar thing - cause stalemate instead of finding a mate in 2, for instance. In the case of HIARCS, I found that changing the search to brute force "solved" the problem. In other words, the engine correctly found the mate in 2 and not the stalemate.

This got me thinking as to whether changing the search algorythm in the Saitek Cosmic / Maestro to brute force may produce the same result. Of course, I no longer possess a unit to test, however there is a position on the internet that demonstrates Maestro drawing a completely won game in this manner. Here is the position, taken from Overtom's weblog:

http://www.xs4all.nl/~tluif/weblog/08FEB05.html

[d] 6b1/8/7p/K5kP/4n3/1q6/5p2/8 b - - 0 1

I would greatly appreciate if anyone owning either of these two machines (Cosmic or Maestro) could check to see if it plays Nc6 in this position when set to "brute force" mode. I think it might need to be tested a number of times on takeback, since I believe there is a certain randomness to the moves the program selects (in other words, it could both mate and stalemate in brute force mode).

I would be very interested to get an authoritative answer on this, as I may consider getting a Maestro if the bug does not manifest itself in brute force mode.

Inquisitive Regards

Jonathan

[JonP01]

And a second position taken from the same website. Again Maestro chooses stalemate instead of any number of ways to force mate.

[d] 8/6P1/8/8/4N1BP/6R1/1PP5/2K2k2 w - - 0 0

[Steve B]

hi Jon
well i own the Cosmic as i guess you already know
i can test the positions tomorrow after the GREAT GRUDGE MATCH concludes


for now..Team RF05 will be going into "media blackout mode " and concentrating on tomorrows historic event

Secretive Regards
Steve

[JonP01]

Hi Steve,

Yes I checked your collection before posting If you could check the two positions that would be great. If you don't mind, please try a number of takebacks on each of the two positions to eliminate the possibility that the "fix" might be nothing but the random move generator at work. I seem to remember checking this on my Cosmic a few years back and I don't think it stalemated every single time. However, the idea in this instance of course, is that it will never, ever stalemate in brute force mode. If this test is successful, I might PM you with a just a couple of other very simple tests - but only if brute force appears to resolve the issue.


Hopeful Regards

Jonathan

[Steve B]

Hi Steve,

Yes I checked your collection before posting If you could check the two positions that would be great. If you don't mind, please try a number of takebacks on each of the two positions to eliminate the possibility that the "fix" might be nothing but the random move generator at work. I seem to remember checking this on my Cosmic a few years back and I don't think it stalemated every single time. However, the idea in this instance of course, is that it will never, ever stalemate in brute force mode. If this test is successful, I might PM you with a just a couple of other very simple tests - but only if brute force appears to resolve the issue.


Hopeful Regards

Jonathan

ok Jon

but in your first position something is wrong as Black cannot play NC6..or are you saying it will not only stalemate but make an illegal move as well??
Regards
Steve

[JonP01]

Sorry, my mistake. Nc5 is correct. So far as I know, it only stalemates - no illegal moves!

Clarification Regards

Jonathan

[Steve B]

HI Jon

[d] 6b1/8/7p/K5kP/4n3/1q6/5p2/8 b - - 0 1

in this position sure enough the Cosmic makes the move Nc5 and declares a stalemate
i tried this on several levels including Infinite and even the Mate in 2 Level!


[d] 8/6P1/8/8/4N1BP/6R1/1PP5/2K2k2 w - - 0 0

in this position however the Little Cosmic redeems itself
on every level i tried..Infinife,Mate In 2,40/2hrs,1 min a move..it always plays h5 and declares a mate in 2

i tried each level taking back the move 3 times on each level and the move was always h5 with the mate announcement

Homework Assignment Completed Regards
Steve

[JonP01]

Hi Steve,

What a pity. Thanks for that. Seemingly no Maestro for me then. So you were absolutely 100% certain that the brute force alogrythm was enabled?

Just double checking regards

Jonathan

[Steve B]

Hi Steve,

What a pity. Thanks for that. Seemingly no Maestro for me then. So you were absolutely 100% certain that the brute force alogrythm was enabled?

Just double checking regards

Jonathan

yes of course
you think you are dealing with a novice here?

Sheesh Regards
Steve

[JonP01]

No But when one is kissing a potential new dedicated computer goodbye, well you must know that the survival instinct kicks in

So, anyone know Craig Barnes's email address?


Not holding out hopes for an improved Maestro II Regards


Jonathan