Aalborg Command Module Operating Manual page 42

The protocol described below allows for communications with the unit using either a
custom software program or a "dumb terminal." All values are sent as printable ASCII
characters. The command parameters are delimited by a space character and the com-
mand string is always terminated with a carriage return character, (line feeds are auto-
matically stripped out by the SDPROC).
The structure of the command string:
Cmd Arg1 Arg2 Arg3 Arg4 [CR]
Where: Cmd
Arg1 to Arg4
[CR]
When a valid command is sent to the SDPROC the unit will respond as indicated in the
table. If an invalid command is sent, the unit will respond with "[string] ERROR" where
"string" refers to the characters that were received by the SDPROC (NOTE: the length
of the string has to be at least two characters long).
Several examples of both valid and invalid commands follow:
1. Turn on the check sum:
The unit will reply:
2. To transmit data every 30 sec:
The unit will reply:
Followed by:
(This will repeat every 30 sec and assumes a two channel SDPROC with error check-
ing enabled. XXX.X is the flow reading in % FS; I is internal reference for set point; YY
is the two character check sum).
3. Transmit Set Point to channel #2: SP 2 50.0[CR]
The unit will reply:
4. An example of an invalid command to a 2 channel SDPROC:
The unit will reply:
(The channel number greater than 2 and desired flow greater than 105.0 are
both invalid).
The two or three characters command
from the table below.
The command arguments from the table below.
Multiple arguments are delimited by a space character.
Carriage return character.
36
CS 1[CR]
CS 1 OK[CR] [LF]
CD 30[CR]
CD 30 OK[CR] [LF]
#1:X XX.X%I #2: XXX.X%I[CR][LF][Y Y]
SP 2 50.0 OK[CR] [LF]
SP 3 106.0[CR]
SP 3 106.0 ERROR:WRONG CHN#[CR][LF]