HP 8924C - Page 205

205
S:\HP8924C\USRGUIDE\BOOK\chapters\hpibstat.fb
Chapter 4, Status Reporting
Status Reporting
Writing the Service Request Enable Register
The Service Request Enable Register is written with the *SRE Common
Command. The *SRE command sets the bit pattern (bits 0-5 and 7) of the Service
Request Enable Register. The Service Request Enable Register allows the
programmer to select which condition(s), as defined by bits 0-5 and 7 of the Status
Byte Register, will generate a Service Request on the HP-IB bus. The Test Set
always ignores bit 6 (binary weight 64) of the bit pattern set by the *SRE
command.
The bit pattern set by the *SRE command is determined by selecting the desired
condition(s) from the Status Byte Register, setting the value of the bit position(s)
to a logical one, setting the value of all non-selected bit positions to a logical zero,
and sending the binary-weighted decimal equivalent of bits 0-5 and 7 after the
*SRE command. For example, if the programmer wished to have the occurrence
of a message available in the Output Queue (bit position 4 in the Status Byte
Register) and the occurrence of a condition in the Hardware# 2 Status Register
(bit position 1 in the Status Byte Register) to generate a Service Request on the
HP-IB bus, the binary-weighted decimal value of the bit pattern for the Service
Request Enable Register would be determined as shown in
table 21.