Remote Read - Chauvin Arnoux C.A 43 FILEDMETER Mode D'emploi

Transmission protocol: pseudo X ON/X OFF
The transmission is done on two optic fibres :
- RxD Reception of data
- TxD Transmission of data
This interface allows the transmission of the results of the measurement, of the content of
the program memory, or measurement of the state of the instrument.
This transmission is obtained from a command, this may be local, directly from the instru-
ment, or at a distance, from an external control unit.
It is possible to establish a dialogue between the Fieldmeter and a computer equipped with
a serial type RS 232 interface. The operation of the interface is described in the chapter
"DIGITAL OUTPUT".
This readout is sent to the instrument on the RxD input.
The readout consists of sending a special code to the instrument.
If the code transmitted does not correspond to a code known by the letter, the instrument
sends the error code 4 (ER 4) to the Tx output.
The output of the codes will start 100ms max after the last character applied to the RxD input.
As the digital link is not a true FULL DUPLEX, the control commands can not be sent
simultaneously with the emission of measurement parameters.
If the instrument is on emission, you must first send it a transition 0 -> 1 on the input Rx. This
information commands it to interrupt its transmission. Then, when this is terminated, after
sending the end of frame code, the message command is sent. If the latter is sent too early,
it will not be entirely decoded and the instrument will send the error code ER4.
The minimum time separating 2 read instructions is 1.275s.
The distance mode has priority over the local mode.

REMOTE READ

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