For the ASCII protocol only, there is a ‘continuous output’ mode controlled by setting the station number to 998 (stream from power up) or 999 (stream on request).
The SOUT value is continually broadcast at the output rate. The maximum output rate is 300Hz with minimum baud rate of 115200.
The output is switched on and off by sending the standard ASCII ‘XON/XOFF’ control bytes (ctrl‑Q = 0x11 and ctrl‑S = 0x13).
This feature is intended for output to a single, simple serial display device or printer.
It has certain special limitations as follows:
- It can only be used in one-to-one operation, i.e. only one unit on a bus otherwise collisions will occur.
- On a RS485 bus it is not always easy to switch off, as the stop instruction must be transmitted when the device itself is not transmitting: If the output rate is limited by communications speed, then output is virtually continuous and may be impossible to stop.
(N.B. this does not apply to RS232, which has separate transmit and receive connections) - The operation does not start automatically, i.e. an initial Ctrl-Q must be sent. This means that if there is (for instance) a brief power interruption, output will stop (when set to 999).
Previously, once you had set the station number to 998/999 Instrument Explorer would not connect to the device again. Now we can connect and also start/stop and view the stream:
When station number 998/999 is set, there is also an additional page available to set the DP and DPB. Be very careful with this as it can end up breaking settings.
If you wish to change from the defaults (6) then this should be the last thing that you do to the module before doing a save and restart/reboot.