Nidek Medical LM-1800P, Interface Manual

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7
RS-232C Communication and USB Communication
:
Communication Format
2
MLM26*RTZ002F
2.2 Communication Format
Among transmitted data are commands such as “Request to Send” other than measurement data. In a
sequence of transmission of measurement data from the LM to the computer, the computer transmits
“Send Data command” to the LM, and the LM receives the command and sends “measurement data”.
The software on the computer reads the received data strings according to the format information and
then performs necessary processing (for example, display of data on the screen or storage of data on
disks).
* When the Com mode parameter is set to “NCP10”, the transmission and reception of com-
mands are not performed.
This section explains the formats of these commands or measurement data.
Symbols other than ordinary characters in commands or data strings are described as “com-
munication control characters” that are commonly used in data transmission.
These signals are added at the start or end of character strings or to delimit data.
Character
name
Decimal Hexadecimal Description
SOH 1 01H Start of heading character
STX 2 02H Start of text character
ETB 23 17H End of transmission block
EOT 4 04H End of character string
CR 13 0DH
Means the end of the input character string for some software
on the computer.
The CR code is added to the data output from the LM when the
CR code parameter is set to “On”.
The CR code is not added to the character strings transmitted
from the computer.
In addition, whether the line feed (LF: 0AH) code is added or not
after the CR code does not matter.