26.4.10.2 Executing a Single-Step Command

Once the PTG is in Single-Step mode, setting PTGSTRT = 1 will cause the PTG to execute the command pointed to by PTGQPTR and then halt. Once this step command has been executed, PTGSTRT is cleared by hardware and can be set again to execute another command. PTGQPTR will then point to the next command to execute; however, its value can be changed while PTGSTRT = 0, allowing single-stepping to take place at any queue location.

Note: PTGSTRT can be cleared manually during single-step execution, halting the sequencer. This is only effective when the currently executing command is waiting for input from an external source or a timer match, as all other commands will be allowed to complete.