Steps into source code.
count(optional) specifies the number of times the command is to be repeated. If no count is specified, executes a single assembly instruction.
Executes the next available instruction in C or assembly source code then halts. If an action enters an area with no source code, the debugger continues stepping until source code (somewhere) is reached. Repeats count times.
Synchronous from GEL: No
Completely synchronous: No