Use this command to define the contents of the VOLATILE pattern.
Depending on the data format (see :DIG:FORM), each byte contains one,
four or eight bits.
81150A: 2-level patterns can be 2 to 16 Mbit long, 3- and 4-level patterns
can be up to 8 Mbit long.
81160A 1-channel: 2-level patterns can be 2 to 4 Mbit long, 3- and 4-level
patterns can be up to 2 Mbit long.
81160A 2-channels: 2-level patterns can be 2 to 2 Mbit long, 3- and 4-level
patterns can be up to 1 Mbit long.