Elgas EDT 101, Руководство пользователя

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4.4.5 Stop measurement.
Forcing the Stop measurement coil ON stops the single measurement, continuous
measurement or datalogging if this is in progress, otherwise the function has no effect.
4.4.6 Start single measurement.
Forcing the Start measurement coil ON starts a single measurement of temperature. The
query is responded immediately, but the measurement takes 120 ms. During the time when
the measurement is in progress, bit 0 (Measurement in progress) in the Status register is set.
Polling this bit enables a host to determine the end of the measurement. Until the
measurement is completed, the registers in the Measured variables section contain the old
values. These are replaced with new values as soon as the measurement is complete.
After the measurement is completed, bit 14 in the Status register is set when a sensor or
analog-to-digital converter failure is detected.
A typical procedure executed by the master to measure temperature is shown in Chyba!
Nenalezen zdroj odkazů. 6. The master sends a query with the function Start measurement.
The transducer responds and starts the measurement simultaneously. After receiving the
response, the master waits until the measurement is finished. The master can either wait for
a fixed time which is equal or longer than the measurement time (see paragraph 4.3.3) or it
can poll bit 0 (Measurement in progress) of the Status register to determine the end of the
measurement (see paragraph 4.3.6). As soon as the fixed time interval elapse or Status register
bit 0 is reset, the measurement is complete and the master reads the value of measured
temperature.
Query
FC=45h
Query
FC=03h
Query
FC=03h
Response Response Response
Measurement in progress
Start measurement Read measured pressure Poll Status byte (optional)
Communication
Measurement
time
Figure 6. Using Start measurement command.
4.4.7 Start continuous measurement.
Forcing the Start continuous measurement coil ON starts a continuous measurement of
temperature. During the continuous measurement mode, the temperature measurements
are started and measured variables are updated automatically at the fastest possible rate. The
update rate is 125 ms.
During the continuous measurement, bit 3 (Continuous mode) in the Status register is set.
If the continuous measurement mode is required to be entered automatically after power-up
or reset, value 0x01 should be written into the Default operation mode register (register
no. 40064) and Write EERPOM command must be issued.