Operation Manual

14
Since the meter does not handle a great deal of data, the RS-232 communications link has
been optimized to allow the user, through very simple instructions, to control and request
data from the meter. Refer to Specifications section for RS-232 Settings (Baud, etc).
Data transmitted/received is in standard ASCII format, and all numerical values are in BCD
format. All commands sent to the unit should be terminated with a “Carriage Return”
character (<CR> or in hexadecimal, 0x0D). All commands and responses are echoed by
the unit for confirmation of communication, and are terminated with “Carriage Return” and
“Line Feed” characters (<CR><LF> or in hexadecimal, 0x0D0A). If an invalid command is
received, the unit will respond with the characters “??”.
The following section describes the protocol used by the meter in detail:
R - READ
The READ command allows the user to read system settings and
data.
Usage:
R(Location)(CR)
Where:
R - READ command
Location - contains two digits indicating the data location to be
read
CR - Carriage Return
Example:
Data Sent Data Returned Meaning
R08<CR> R08<CR><LF> Echo of Command Sent
10.25 mmHg<CR><LF> 10.25 mmHg measured
W - WRITE
The WRITE command allows the user to update the system settings.
Usage:
W(Location – 2 digits)(Data – 5 digits)(CR)
Where:
W - WRITE command
Location - contains two digits indicating the data location to be
written
Data – five-digit field containing the data to be written at the
Location set above
CR - Carriage Return
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