Pitney Bowes J640 - Manual (Page 155)

Inquiry Response (ENQ Response)
Printer status is returned to the host in a 3-byte (3-character)
sequence. The first byte is the ENQ character. The second
and third bytes are printer status codes. Refer to the ENQ
Reference Tables for the meaning of the response characters.
Example:
E
AB
The status codes (A and B in this case) are ASCII equivalents
to the hexadecimal bits that represent the various types of
status responses. This response indicates that the printer is
online (Character A) and that there is a stock fault
(Character B).
The following graphics can be used as a quick reference for
the Status of Byte #2 and Byte #3.
J640 Programmer’s Manual
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