New MAME engine gives crackling noise in speaker

[Håkan Löfgren]

Hi,

I have installed picochess v3 Lite a while ago on my DGT Pi/Smartboard and it works really well - great product!

As I own a RISC 2500 computer, I have added this ROM to picochess by copying the ROM to mame_emulation/roms and updating the engine.ini file with the RISC2500 info from engines_addon.ini. All other files (lua, uci, etc) pertaining to this engine have I left untouched. 

As soon as I select RISC2500 from the clock engine menu, a constant crackling noise is emitted from the attached hamburger speaker. I can play a game with the engine and hear the move announcements but the noise is present all the time. 

If I, for instance, choose Stockfish or the MAME engine Roma32 all works fine with no bad noise from the speaker. 

What can be the problem?

[Scally]

Hi Håkan,

You are correct with adding risc2500.zip to mame_emulation/roms

As well as your engines.ini entry in the armv7l folder, you also need an engine file and a uci file.

Your risc2500 engine file should look like this:

#!/bin/bash

cd /opt/picochess/engines/mame_emulation; /opt/picochess/engines/mame_emulation/mess -skip_gameinfo -lightgunprovider none -nowindow -plugin chessengine risc2500   (You May have to add  -sound none  before the  -plugin  to stop the crackling)

And you risc2500.uci file like this:

[01-5m game]
level = 5 min/game
PicoTimeControl = 5 1

[02-10m game]
level = 10 min/game
PicoTimeControl = 10 1

[03-15m game]
level = 15 min/game
PicoTimeControl = 15 1

[04-30m game]
level = 30 min/game
PicoTimeControl = 30 1

[05-60m game]
level = 60 min/game
PicoTimeControl = 60 1

[06-1s move]
level = 1 sec/move
PicoTimeControl = 1

[07-5s move]
level = 5 sec/move
PicoTimeControl = 5

[08-10s move]
level = 10 sec/move
PicoTimeControl = 10

[09-30s move]
level = 30 sec/move
PicoTimeControl = 30

[10-60s move]
level = 60 sec/move
PicoTimeControl = 60

Cheers,

Al.

[Scally]

Hi,

I told you wrong for the risc2500 engine, it’s:

#!/bin/bash

cd /opt/picochess/engines/mame_emulation; SDL_VIDEODRIVER=dummy /opt/picochess/engines/mame_emulation/mess -skip_gameinfo -lightgunprovider none -video none -sound none -plugin chessengine risc2500

Al.

[Håkan Löfgren]

Thanks a lot Scally,

I added -sound none to the risc2500 engine file according to your post and it fixed the problem!!

The engine file and the uci file was already installed on the pi lite image, so it was really easy to just add the RISC2500 ROM and update the engines.ini file ;-)

The uci file has also entries for style and strength in addition to the levels. Style is set to offensive and Strength to moderate in the preinstalled file (can be changed) so the engine currently plays attacking games and finds mating nets quite fast. 

/Håkan