Canon LBP-1760 Service Manual page 65

is rotating at the prescribed speed or not.
The CPU notifies the scanner failure to the video controller in the following cases:
1) The /BDI signal is not input for about 100ms continuously at the scanner motor start or
stop.
2) The period in which the /BDI signal cycles deviate vertically from the specified cycle is about
10mm (print distance equivalent) during masking or non-masking in the normal rotation.
During non-masking in the normal rotation, if any /BDI signal cycle deviates from the specified
cycle, the CPU assesses a /BD error.
CHAPTER 2
2 - 27