Acoustic Control Keyword
MDSP bit 40 modifier, the bit that toggles Acoustic Control. Reset if N = 0, otherwise set. All MDSP modifiers are both parameters and switches. If N is missing the bit is set and the mode is active.
Acoustic Control was implemented in the days of PDP-11s and tape machines, while the use of tapes outlasted the PDPs both are certainly redundant these days with the use of digitized wave files. This mode was for acoustic only experiments and essentially used DMastr to gather and record responses with no visual stimulus.
If a polled input device (see Input) is being used then you may want to reduce the default polling rate from 10ms.