Brother Facsimile Equipment MFC7420 - Manual (Page 201)

Confidential 9-13
(5) Command reception [checking the NSF and DIS after transmission of NSS and DCS]
Code 1 Code 2 Causes
50 01 Vertical resolution capability changed after compensation of
background color.
(6) ID checking
Code 1 Code 2 Causes
63 01 Password plus "lower 4 digits of telephone number" not
coincident.
63 02 Password not coincident.
63 03 Polling ID not coincident.
(7) DCN reception
Code 1 Code 2 Causes
74 DCN received.
(8) TCF transmission/reception
Code 1 Code 2 Causes
80 01 Fallback impossible.
(9) Signal isolation
Code 1 Code 2 Causes
90 01 Unable to detect video signals and commands within 6 seconds
after CFR is transmitted.
90 02 Received PPS containing invalid page count or block count.