jumper settings for sound on TT?

[Randy]

Someone mentioned that there may be jumpers that allow the sound circuit to function, is that true?  Sounds strange but if there is a jumper for sound, can someone tell what and where it is?  Thanks

[mdivancic]

TT page from Zogging Hell!!!

 

...and to quote:

 

Quote

DIP Switches on TT motherboard

As far as I'm aware only switch 7 has any useful effect on the TT, allowing you to select whether either a high density or double density disk drive is in use. Switch 8 can be used to turn off the DMA sound hardware (though why you'd want to do this is beyond me!). Switch 5 is used by the CaTTermaran to activate it. Switches 1 - 4 and 6 have effects which are so far undocumented. If you have a clue what these do then please get in touch.

 

[lp060]

Switch 8 -> on = Disables the DMA sound hardware

My TT arrived with this switch set wrong by the dealer.

 

Not sure where his switch 5 info came from, but Cattamaran manual states:

Set DIP switch # 1 to ON (as shown). This informs the system that you have installed a CyReL CaTTamaran 48 MHz accelerator module in your Atari TT030.

Edited December 13, 2020 by lp060

[Cyprian]

22 hours ago, Randy said:

Someone mentioned that there may be jumpers that allow the sound circuit to function, is that true?  Sounds strange but if there is a jumper for sound, can someone tell what and where it is?  Thanks

There is no dedicated jumper which can turn sound off on the hardware level.

TT and Mega STE dip switches just inform the TOS whether your would like to 'disable' DMA sound or switch from HD to DD floppy density.  Based on dip switches the TOS sets appropriate variables "_SWI" and "_SND". And then, based on those cookies, the TOS will not use DMA sound or HD floppy density.

 

Third-party applications (lice Catamaran) can also use "_SWI" variable to its own purposes.

Edited December 13, 2020 by Cyprian_K