Sound Simm Slot on 502

[stlscott]

I've been reading post after post but not quite finding the detail I am looking for.  I have a standard 502 board (see pic).  This is on my Triple Double Diamond S2000.  I was wondering which sound SIMMS can I use with it as I see lots are available?  I know that you can add an additional (enhanced) sound board on it as well, not sure what the differences are or what I need...  The options are confusing and most of what I find is "troubleshooting" sound issues, and I'm really looking to understand compatiblity with the base 502 board (for the SIMMs) and what you get with the daughter-board (enhanced I think it's called).

Thanks for any help... I'm learning, I swear!

[Tilt]

The sound simm plugs into the multimedia lite ii (MML2) daughterboard.  The daughterboard then plugs into the two empty card connectors on the MPU board.  The simm card slots on the 502 MPU board aren't used for anything.  The 502 MPU will play standard sounds.  With the daughterboard and the correct sound SIMM for your game theme you can play "enhanced" reel spin sounds, roll up sounds, etc.

If that's a picture of your MPU board I'd get rid of that Varta battery before it starts leaking and damages your board.

[stlscott]

The sound simm plugs into the multimedia lite ii (MML2) daughterboard.  The daughterboard then plugs into the two empty card connectors on the MPU board.  The simm card slots on the 502 MPU board aren't used for anything.  The 502 MPU will play standard sounds.  With the daughterboard and the correct sound SIMM for your game theme you can play "enhanced" reel spin sounds, roll up sounds, etc.

If that's a picture of your MPU board I'd get rid of that Varta battery before it starts leaking and damages your board.

Thank you for the clarification, someone else told me that the SIMM slots on the 502 could take a sound card and I didn't think that was the case.  Why are there "there" if they aren't usable?  I always wonder that kind of stuff.

As for the Varda, it's on my list of things to do.  After removing it from my 1270, though, I've been a little gun-shy.  I've had several issues on the 1270 after the Varda removal (and u16) and no issues before.  It doesn't boot unless you raise and lower the door-switch many times (after it's been on for a while)... it got the segment-display error, just all kinds of crazy stuff...

[Tilt]

I'm sure they were designed so games that required more memory could be written to SIMM cards instead of EPROM chips, but I'm not aware of any games that actually required or used it. 

As for the 1270 Varta removal, most all go without any issues, but occasionally one will have issues after removal.  I'm not sure why that is.  Someone said to re-install U16 and the battery.  Let it fully charge, then turn on the machine.  After it boots then shut it down and remove it again and it will be fine.  I'm not sure if that actually worked for someone or not and don't remember who said it either. 

The only problem I've heard of removing 502 batteries is when they've already leaked some and removing the battery takes some of the traces up with it.  Eventually it would have quit anyhow when the electrolyte finished eating through the copper traces.  For clean boards though, no problem removing it.

[stlscott]

I'm sure they were designed so games that required more memory could be written to SIMM cards instead of EPROM chips, but I'm not aware of any games that actually required or used it. 

As for the 1270 Varta removal, most all go without any issues, but occasionally one will have issues after removal.  I'm not sure why that is.  Someone said to re-install U16 and the battery.  Let it fully charge, then turn on the machine.  After it boots then shut it down and remove it again and it will be fine.  I'm not sure if that actually worked for someone or not and don't remember who said it either. 

The only problem I've heard of removing 502 batteries is when they've already leaked some and removing the battery takes some of the traces up with it.  Eventually it would have quit anyhow when the electrolyte finished eating through the copper traces.  For clean boards though, no problem removing it.

Thank you for the update on 1270 - it has been really strange with issues post-removal.  Another person on this site recommended I remove a couple of different transistors and jumper a location to resolve this 5v boot issue, as a work-around. 

Another question for the Sound SIMM... I've ordered a couple of Enhanced Sound boards to add to my 502.  Can I install any Sound SIMM or is there a compatibility chart?  I thought it might be fun to use the Munsters or Wild Thing sound simm in a standard game... 

[Stayouttadabunker]

You might want to get in touch with the member that tested every SIMM card, Yoeddy1.

[sixcardmark]

For general rule only SBs with lower numbers will allow for sound simm swap. SB100001 thru SB100099 for the most part, any higher number and you will be stuck with the DSV00042.

[stlscott]

For general rule only SBs with lower numbers will allow for sound simm swap. SB100001 thru SB100099 for the most part, any higher number and you will be stuck with the DSV00042.

Interesting, wonder if IGT started locking them down to specific games at some point...

[stlscott]

Hopefully I bought the right daughter-board to add a SIMM to a game.

[sixcardmark]

Yes that is correct board.  I hope your 502 board has been modified because enhanced sound normally sucks on 502 boards.

[stlscott]

Here's my 502 board, how would I know if it's been Modd'd  and Yes I will be removing the Varda in the next week.

[sixcardmark]

If you didn't send it to someone to modify or buy it already modded then it's probably not been modified.

[lookes]

Does not look modified.

[Retro tech repair]

The simm slots on the mpu are wired in parallel with the main buss. They were included for expansion but never used. If you plug a simm in there and it tries to send data while the machine is accessing something else it will stop the board from booting.

[stlscott]

The simm slots on the mpu are wired in parallel with the main buss. They were included for expansion but never used. If you plug a simm in there and it tries to send data while the machine is accessing something else it will stop the board from booting.

Thank you - Good to know!