Toshiba B-EP Series Interface Specification page 619

Notes (1) The status is returned only to the interface which sent this command.
(2) The printer returns the same status, regardless of whether or not the compatible
mode for the B-SP series is set.
(3) After receiving the Status Request Command, there may be a maximum of
20-msec. delay until the printer sends a status.
(4) At least, a 20-msec. interval must be given between the transmissions of the Status
Request Command. If the next Status Request Command is transmitted within 20
msec., the printer may fail to receive it.
Example [ESC] WB [LF] [NUL]
CHAPTER 8 ESC/POS MODE (INTERFACE COMMANDS)
8-92
B-EP Series