Using a terminal program, issue the command “v rs232_mode=xx”, where xx is defined below:
Model | xx |
M100 | 35 |
M200 | 35 |
M100A | 43 |
M200A | 43 |
M300 | 43 |
M400 | 43 |
M700 | 43 |
The software uses the RTS signal from the SBC40 to control the multi-drop interface hardware. The software turns this signal on (logic high) prior to transmitting data, and turns it off within 1 second after the last character has been fully transmitted.
Software Setup for RS-232 Multi-Drop (E-series analyzers)
Every analyzer on the multi-drop chain has to have a unique ID number. Default ID numbers are the analyzer model number:
M100E – ID 100
M200E – ID 200
M300E – ID 300
M400E – ID 400
However, if more than one analyzer of the same model is used, the ID numbers have to be changed accordingly.
To enable multi-drop in the software, follow this command sequence (this example assumes that COM1 is used for multi-drop use):
SETUP – MORE – COMM – COM1 – EDIT mode and select NEXT until
COM1 MULTIDROP MODE appears and then select ON, press ENTER, then 4x EXIT.
The COM1 Mode should now show a number that is 32 higher than before.
If you wish to operate an E-series analyzer in series with older models, keep in mind that the baud rate for all COM ports needs to match. A-series analyzers support a maximum baud rate of 19200 baud, whereas E-series analyzers support up to 115 000 baud. Multi-drop performance may degrade at speeds higher than 19200 baud, particularly if cheap, unshielded cables are used. With short, shielded, good quality cables, the maximum baud rate should work.
Hardware Setup for RS-232 Multi-Drop (E-series analyzers)
Whereas A-series analyzers draw their power from within the analyzer chassis, E-series analyzers can supply 5V DC power directly from the rear panel. The E-series multi-drop option includes a small cable converter with open leads to be connected to the screw terminals of the STATUS output connector on the rear panel. Connect the red wire to the screw terminal labeled + on the STATUS connector and connect the black wire to the terminal labeled G on the same connector. Please refer to Figure 4 for proper connection of a multi-drop option (part # 04528).
CAUTION: Do not reverse the wiring, it will destroy the multi-drop circuitry!
