Module Integration Manual
Page 9 of 18
Interrogator RF Board (400.00152.xxxx)
4.4.1
Immediate commands:
These commands include register fetches, EEPROM reads and writes, and other similar
commands that execute within the communications processor. These are executed as they are
retrieved from the input queue and their results are posted to the output queue for transmission.
4.4.2
DSP High Level Commands:
These commands are translated into one or more DSP commands. The DSP commands are
issued and, once all results are received, a high level response is posted to the output queue.
Temperature measurement, calibration, sensor definition assignment, and setting regional limits
are examples of such commands. All functions requiring transmission are subject to being
blocked by the Part 15 timing loops.
4.4.3
DSP Low Level Commands:
These commands are passed to the DSP as the DSP becomes available. The communications
chip does not wait for completion and immediately begins processing the next command. When
the DSP responds, the response is forwarded to the output queue. All functions requiring
transmission are subject to being blocked by the Part 15 timing loops except test mode
commands, such as pulse train and CW TX on.
4.4.4
Automated Measurements
In addition to processing commands from COM0 and COM1 input queues, the communications
chip also runs an internal command thread. This thread optionally sends a heartbeat command
to the DSP once every 2.5 seconds and optionally forces a reset of the DSP if there have been
no responses in the last 10 seconds. This thread measures the Sensirion® humidity sensor, if
one is attached, and posts the results to the MODBUS registers. Finally, if automated
temperature or partial discharge measurements are enabled, this thread scans the list of sensor
definitions for those sensors having automation enabled. Enabled sensors are then measured
as internally generated high level DSP commands. No response is sent to a COM port from
these commands.
4.5
P
ARSING
DSP
RESPONSES
Regardless of the source of a command, all responses from the DSP that contain sensor data
are parsed. The data is validated and calibrated, then inserted into the MODBUS registers. In
this way, MODBUS registers are updated by the most recent measurement request, regardless
of whether it was internally or externally generated.
