Welch Allyn LC101 CO2 Module - User Manual - Manual (Page 26)

LC101 CO
2
Module OEM Implementation Manual
Page 26 Confidential Welch Allyn OEM Technologies
System EEPROM
The system EEPROM contains manufacturing and operational data that is necessary for the
LC101 Module to function. A limited number of these system parameters may be specified by the
OEM. These include
• data format
• start up mode
• initial pump flow rate
The data format options are 7 and 8 data bits (default is 7E1).
The start up mode options are auto run, measurement, standby and fault (default is standby).
The initial pump flow rate option allows the host to specify the default pump flow rate in
milliliters per minute (default is 150 ml/min).
Packet Structure
Transmission of host commands and Module responses is via packets. The following byte
structure represents a packet.
Packet format:
< start of text (STX) 02h
X identifier 1*(ASCII)
xx
n
data n(hex char)
yy CCITT/CRC code 2*(ASCII)
> end of text (ETX) 03h
ASCII characters have values in the range of 00h to 7Fh. The identifier is case sensitive.
Characters between 00h and 20h are reserved as control characters.
Transmission of all packets starts with a “<” STX control character and ends with a CCITT/CRC
code and “>” ETX control character. Between STX and ETX is an identifier and n bytes of ASCII
data. The length of the packet is defined by the identifier character. Packet length cannot exceed
25 bytes with a maximum of 20 bytes of data allowed. Packets without the STX control character
are ignored. The CCITT/CRC code is calculated on values between STX and CCITT/CRC code.
Example:
02h X xx
n
yy 03h