There are two main modes of operation of the MCMTII: the guiding mode and the slewing mode. Additionally, there are some specific modes such as the EEPROM update mode and the parking mode, not yet documented here.
- when guiding, the main task is to provide a constant motor rotation rate. It gives priority to the clocks and backgrounds the processing of the serial link. All commands are replied with an ACK even if they are not processed correctly.
- when slewing, the main task is to provide an accurate positioning. It gives priority to steps counting. Only 2-byte serial commands, with the heavyweight bit high (non-ASCII commands), are processed as interruptions. The list of these commands is just below. During the slewing, a specific timer is used to adjust the number of steps to move to, as function of the time spent to slew. Slewing mode is entered when medium or max speed are used (by physical or virtual hand controller or 'p' command).
- when flashing the EEPROM, commands are 16 bytes long.