User Guide

54A0049_7.0_EN / Leddar Pixell – User Guide 37 | 127
4.4.4. Access to the Communication Protocol
The communication protocol allows you to fetch the currently active alerts from the sensor. To do so, the
CFG_REQUEST_UPDATE request (code 0x0008, see section “Configuration Server Requests” in Appendix
D “Communication Protocol”) must be made to the configuration server. See Table 43 on page 110 for the
definition of the alert structure.
4.5. Sensor Operation Overview
The sensor firmware operates following an internal state machine. This section outlines the cycle of operation
of this state machine.
There are three (3) main states in the sensor: Initialization, Normal Acquisition, and Safe modes.
Initialization mode: The system boots into this state when powered on. The system loads the sensor
configuration and calibration from non-volatile memory. It checks whether the loaded data is coherent. It
performs initial self-tests to detect faults, which lead to Safe mode. If the initialization is successful, the sensor
transitions to Normal Acquisition mode automatically.
Normal Acquisition mode: This is the sensor’s main measurement acquisition and transmission mode.
Lasers are flashing. Pulses are treated through signal processing algorithms and transmitted through the
Ethernet communication port. Self-checks are embedded in the process to detect faults, which lead to Safe
mode. If no faults are detected, the sensor remains in this mode until power is turned off.
Safe mode: The sensor has detected a critical fault that can result in damage to itself, its host, or any
surrounding material or people. The conditions for the sensor to switch to Safe mode are as follows:
• Voltage at the capacitor banks too high
• Pulse repetition rate too high
• Critical supply for eye-safety hardware protection out of range
• General voltages out of range
• Lasers too hot
• CPU too hot
• Power distribution electronics too hot
When in Safe mode, the lasers are NOT flashing, the acquisition loop has stopped, and the
sensor is not outputting any detections. Power consumption is reduced to a minimum. The
Ethernet link is kept alive to inform you of the current status as much as possible.
The only way to exit Safe mode is to power cycle the device.
If the device has recovered from Safe mode and restarted but the critical condition is still present, the unit
will return to Safe mode again.
If the unit returns to Safe mode repeatedly after you power cycle the device, power off the device and contact
LeddarTech’s technical support for further troubleshooting.