Enabling the
Status Byte
A service request (SRQ) will b e generated when any enable bit in the
status byte register is set to \1". So to enable/disable any bits of the
status byte register, you can set bits in the service request enable
register. These bits corresp ond to bits in the status byte. When a
bit is set in the service request enable register it enables that bit in
the status byte to request service. To set bits in the service request
enable register, the
*SRE
command is used. The syntax of the
*SRE
command is :
*SRE
<
n
>
Where,
<
n
>
: decimal number (0 to 255)
For example,
If
<
n
>
is equal to 34 (00100010 in binary), bit 1 and bit 5 are
enabled, as follows.
Bit No. of
Status Byte
MSB LSB
76543210
Bit Pattern
for *SRE command
00100010
In this case, when either bit 1 or bit 5 of the status b
yte is set to \1",
a service request is generated.
The default setting is
*SRE 0
(all bits of the status byte are disabled).
Bit 6 (RQS) is non-maskable, and bits 0 to 3 are always 0 (zero).
Thus, it is meaningless to mask these bits. (The
*SRE
command's bit
pattern for masking bit 6 is ignored, and the
*SRE
command's bit
pattern for masking bits 0 to 3 are accepted, but is meaningless.)
7-22 Remote Control
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