Welch Allyn LC101 CO2 Module - User Manual - Manual (Page 33)

LC101 CO
2
Module OEM Implementation Manual Section 4 - Host/Module Communications
Welch Allyn OEM Technologies Confidential Page 33
Zero Calibration
The Zero Calibration adjusts the IR source current to compensate for detector output changes.
The host is required to inform the LC101 Module when to start sampling 0% CO
2
gas.
When performing a Zero Calibration, the LC101 Module must first be in either Unprotected
'Measurement' or 'Autorun' mode. During the calibration, CO
2
waveform and Breath data will still
be sent to the host.
To get an accurate calibration, the LC101 Module needs to be operating for at least 5 minutes in
measurement or autorun modes. The LC101 will not allow a calibration if this requirement has
not been met. In addition, the calibration should be performed at room/ambient temperature.
After a successful Zero Calibration, the Module updates the zero residual offset constants
located in the
C-Cap EEPROM Memory Map.
Module Responses
The host must initiate all communication with the Module with the exception of periodic CO
2
waveform and breath data packets. The type of response sent is determined by the type of host
command. Responses include:
• status responses
• mode command responses
• simple command responses
• configuration command responses
• calibration command responses
Host Command Description
Perform Zero Calibration
Abort Calibration