Veris 3150 MSP3 Operating Instructions Manual page 100

5. Testing that the instrument is sending the proper command to the external controller.
a) Connect the PC to the PC using a serial cable (you will need a null modem and may
need a gender changer). Turn on the PC and enter data acquisition. The data in
Hyper Terminal should look like this
$U♥♦Ç$U♥♦Ç
The important letter above is the 'U', but the data coming up should match this
character-for-character. The 'U' is the letter the pH Controller is looking for. Press
the engage (1) key on the PC. The data in Hyper Terminal should change to:
$N♥♦e$N♥♦e
Again, the important letter is the second letter, this time 'N'. Pressing the (1) key will
toggle this from 'U' to 'N'. Depending on settings in your controller, there may be
slight variations in the specific characters. The main issue is whether or not any
characters are transmitted.
b) Exit data acquisition. Connect the external pH Controller to the PC using the
Controller's cable. Go back to data acquisition in the PC. If everything is working
properly, the pH readings should be something other than "-1.00" and the message
will read "1 TO START" or "INIT ERR". Wait 10 seconds, disconnect the external pH
controller's serial cable from the PC, and connect it to the PC's serial port. The data
coming in from the external pH controller will be the same as in 3> above if the
message read "INIT ERR", but will look something like this if the message read "1 TO
START":
7F -236 -284 39
7F -236 -285 3A
If the message has changed, everything is working properly. If it has not, the
message being sent from the PC to the external Controller is not being received.
To summarize, the external pH Controller sends a report starting with '7E' until it receives
the command '$U♥♦Ç' from the PC. When the external Controller receives this command,
the reports will start with '7F'. At this point, the external controller waits for a command
starting with '$N' or '$G' from the PC to initialize its position and start cycling. If the external
controller never receives the '$U♥♦Ç' command, it stays in the '7E' state and will not cycle.
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Pub. # OM20-MSP3-3D