EXFO FTB-2 - Manual (Page 367)

IEEE 488.2 and Specific Command Reference
FTB-2 and FTB-2 Pro 357
IEEE 488.2 Required Commands
Response(s) RegisterValue:
The response data syntax for <RegisterValue> is
defined as a <NR1 NUMERIC RESPONSE DATA>
element.
The <RegisterValue> ranges from 0 through 255.
The <RegisterValue> value, expressed in base 2
(binary) represents the bit values of the Status
Byte Register. See the contents of this register
below.
Example(s) *STB? returns 68
where 68 = (bit MSS and bit EAV)
See Also *SRE
*SRE?
*STB?
Bit Weight Meaning
N.U. 128 Not used
RQS/
MSS
64 ReQuest Service (read by serial
polling)/MaSter Summary bit
(read by *STB?)
ESB 32 Event Summary Bit Enable
MAV 16 Message AVailable Enable
N.U. 8 Not used
EAV 4 Error / Event AVailable Enable
N.U. 2 Not used
N.U. 1 Not used