DRS WJ-8611, Инструкция по установке, эксплуатации и обслуживанию

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WJ-8611 DIGITAL VHF/UHF RECEIVER
REMOTE CONTROL 4-25
receiver are passed through to the receiver’s Status Byte Register to
generate a service request (SRQ) over the remote interface. The structure
of the register pairs allows a programmer to mask specific bits, controlling
which events are permitted to cause a service request to be sent.
The Status Byte Register and its Service Request Enable Register comprise
the top level register pair that monitors the status of the lower level
registers. The generation of the service request is based on the inputs to
the Status Byte Register and the setting of its Enable Register. The
ANDed combination of bits 00 and 05 are logically ORed to determine the
setting of bit 06 (RQS). When the RQS bit is set, a service request is
asserted.
Table 4-4 describes the Bits of the Status Byte Register that are
defined in this configuration.
4.6.1 STATUS BYTES
The information that follows describes the operation of the SRQ interrupt,
and the STB? query. The operation of these is very similar. The SRQ
interrupt allows the controller to establish which event has caused the
receiver to assert the SRQ. The “*STB?” query response includes similar
information, as detailed below.
SRQ - For RS-232 operations, the SRQ is a one byte control character
(ESC) initiating a service request. When SRQ is generated, it is
immediately followed by the output that is the decimal equivalent of the
enabled bits of the Status Byte Register, if enabled. This clears the SRQ
and the Status Byte Register. For IEEE-488 operations, the SRQ is
asserted by setting the dedicated SRQ line of the interface. The *STB?
query or a serial poll is then sent to obtain the source of the request. A
serial poll clears the Status Byte Register, the *STB? query does not. The
evaluation of each bit in this status byte is in
Table 4-4 .
*STB? Query - The Status Byte Register is also read using the *STB?
query. Sending *STB? does not clear the SRQ status line or the Status
Byte Register.
The Service Request Enable Register allows the status bits to generate
service requests. Setting a status bit sets service request only if the
corresponding enable bit is set. Service Request Enable register bit six is
ignored and reported as zero. This bit would correspond to the RQS bit of
the Status Byte Register which triggers a service request.
Courtesy of http://BlackRadios.terryo.org