Here is where you'll find information on the new firmware releases for the uMMC Serial Data Module.
S K 1- sets the uMMC into data logging mode on next boot.
S Z 1- sets into low power mode.
Below is an example
UMMC.CFG file (put it in the root of the SD card) to put the uMMC into data logger mode. The uMMC will automatically read the configuration and be in data logger mode.
S D 6
S K 1
S Z 1
D6 K1 Z1