I'm not Berger, but what he told me, he asked around for someone to do a test on Novag Primo after I found a bad bug in Novag VIP. He does not have any Novag Primo (yet) for dumping the ROM.

The bug in VIP: If you press GO right after inputting your own move, the VIP replies by doing a move with the user's pieces instead of its own.

Where is the promlem? Damaged ROM?

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No, a bug in the software.

Perhaps there's a 2nd revision of Novag VIP where the bug is fixed. The MCU in the one dumped by Berger is 31Y0C81F.

I cannot remember but do you have to push "Go"? Or only type the move ie e2-e4 ... I think, "Go" was switching sides?!

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Hello,

In VIP notice :

After the above procedure you may enter your move as White using the keypad; for example E2-E4 is entered by pressing:
E5 B2 E5 D4
You do not have to press ENTER as the VIP detects your completed move and will immediately start computing its reply. When the move
has been chosen it remain on the LCD display. If you wish to cancel your move your may press the TRACE BACK Key.
Note: Since the VIP has no chess board on which to indicate its moves you will have to make all the moves on your own to reflect the
actual game going on inside the VIP's memory.

9) GO Key
The GO Key is used to enter a command or to exit from a Special Function and has the following uses:
a) to make the VIP compute for the side to move
b) to terminate the move search (only while the VIP is computing) and force it to make the move it currently considers the best. Please
allow the VIP at least 5 seconds of search time before pressing this key so that the VIP has time to compute a reasonable move.
C to exit from the SET UP mode
d) to exit from the VERIFY mode
e) to exit from the SET LEVEL mode

Cordially.

It seems this is not the only bug.

When testing underpromotions for the plugin, I reached the following position:
5R2/8/5K1k/8/8/8/8/8 w - -

If you now enter the move Rf8-h8#, the display of the VIP just goes blank instead of showing a mate - you have to press e.g. [C/CB] to continue.

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Interesting.
Regarding the previously commented, all of us who have had a Novag VIP know that you should not press GO after entering the move. hap did it by accident, and I purposely tested it with the "physical" Novag VIP, and we noticed that this bug occurs. And I also think it is a bug, and not a user mistake, because the program should avoid this situation. Otherwise you can still play with illegal moves in the stored move train. It is absurd.

Best,
Gerardo

Hello,

Why you do not compare VIP and SVIP roms (disassembled of course) ?
It is probably the same code, only the library has exploded in size.

Cordialy.

Good find!
Same bug in my Primo:
After NewGame/Reset I play:
b1-a3+GO, and primo responds with d2-d4.
/Lars

Hi Lars,

But... I don't consider that a bug... you simply cancel your move (by pressing GO key) and ask Novag Primo to make the move. And it is a legal move for white. Or does d2xd4 appear on the LCD as in the case of Novag VIP?

I mean "d2xd4" instead of "d2 d4".

Best,
Gerardo