Pioneer 2TM - Manual (Page 66)

Updating and Reconfiguring AROS
Set the FrontBump and RearBump parameters to the number of bumper segments for the
front and rear bumpers, repectively; or to 0 if you don't have a particular bumper. For
pre-AROS 1.6 robots, you don't need to set these values to have them work with AROS
1.6. The number of segments is used to isolate the bumper bits, if any, and to apply
InvertBump as needed, so that a triggered bumper is reported as digital 1 regardless of
the hardware, and is reported as such in the standard SIP. IOpac, on the other hand,
simply reports the bit-mapped states of the input bytes associated with the bumpers,
regardless of hardware.
The FrontBump and RearBump byte values also are reported near the end of the
CONFIGpac.
If for any reason you remove a new-style bumper from your robot, you MUST reset the
InvertBump FLASH value or disable BumpStall for that bumper. Otherwise, the robot will
stall incessantly.
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