HP 8920A Programmer's Manual page 301

Table 27 Determining the Service Request Enable Register Bit Pattern
Bit Position
Logical Value
Binary Weighting
Decimal Value
NOTE:
7 6 5
0 X 0
128 X 32
0+ 0+ 0+
Example
OUTPUT 714;"*SRE 18"
The decimal value of the bit pattern must be a positive integer in the range of 0 to 255.
Sending a negative number or a number greater than 255 causes an
HP-IB Error: -222 Data out of range.
Clearing the Service Request Enable Register
The Service Request Enable Register is cleared by sending the *SRE Common
Command with a decimal value of zero. Clearing the Service Request Enable
Register turns off service requests.
4 3 2
1 0 0
16 8 4
16+ 0+ 0+ 2+
Chapter 5, Advanced Operations
HP-IB Service Requests
1 0
1 0 X = ignored by the Test Set
2 1 X = ignored by the Test Set
0 = 18
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