U1MB device control question

[jc13]

I don't have any particular application in mind, but I was curious if it was possible to control the S0/S1 (or M0/M1) lines from within the OS or BASIC (i.e. outside of the U1MB setup screens).  I'm guessing there would need to be some sort of driver/handler to do this, but couldn't find an answer.

Edited September 12, 2019 by jc13

[flashjazzcat]

11 minutes ago, jc13 said:

I don't have any particular application in mind, but I was curious if it was possible to control the S0/S1 (or M0/M1) lines from within the OS or BASIC (i.e. outside of the U1MB setup screens)

No: it's not possible. Once the configuration is locked (i.e. when one leaves the setup menu), the state of the S0/S1/M0/M1/VB signals is fixed until the next time one presses the system RESET key. One could certainly write a driver to access the NVRAM where the actual settings which control these lines are stored, but this would essentially be a redundant alternative to simply changing the settings in the BIOS setup menu (since the settings are only applied during the transition from the BIOS menu back to the OS).

Edited September 12, 2019 by flashjazzcat

[jc13]

Got it - thanks for the quick response!

[_The Doctor__]

ah but think about it, having a software set up programming method would be quite cool...

some software could be aware of the u1m, do the setup and reset when done... if on re run of program all setting match it simply skips making the changes and doesn't reset. The user wouldn't have to fiddle about and it would be a streamlined experience...

 

could avoid a number of 'these settings needs to be like this but only if that setting was made here for this particular item' discussions.

Edited September 12, 2019 by _The Doctor__