User Manual

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Copyright (c) 2009-2013 RoboPeak Team
Copyright (c) 2013-2016 Shanghai Slamtec Co., Ltd.
Major Working States and Transition Conditions
RPLIDAR has the following 4 major states: Idle, Scanning, Request Processing and
the Protection Stop state.
The translation conditions are depicted in the following figure:
Figure 3-1 RPLIDAR’s Major Status Translation
The Idle state is the default state of RPLIDAR which will be entered automatically
after powering up or reset. Both the laser diode and the measurement system are
disabled in this state, and the whole system is in power saving mode. Once RPLIDAR
enters the Scanning state, the laser diode and the measurement system will be
enabled and RPLIDAR will start measuring distance and sending the result out
continuously.
RPLIDAR will enter the Request Processing state once it receives request packets
from the host system. During processing the request, RPLIDAR won’t perform the
scan operation and won’t send any data out. It will only send out response data
for request needing a response after the required operation has been finished. After
the request has been processed, RPLIDAR will enter other status specified by the
request.
Once RPLIDAR detects something wrong with the device hardware, it will stop the
current operation and enter the Protection Stop state. A host system can still
communicate with an RPLIDAR in the Protection Stop state to query its working
3. Working State and Mechanism
Idle
Scanning
Request
Processing
Protection
Stop
Reset the core
system
No Request
No
Request
No failure
System
Power Up
Request
comes
Partial
Requests
Start Scan
Request
Request
comes
Failure detected
Failure detected