Canon imageCLASS X LBP1238 II Service Manual page 4

2. In the digital circuits, '1' is used to indicate that the voltage level of a given signal is "High", while '0' is used to indicate "Low".
(The voltage value, however, differs from circuit to circuit.) In addition, the asterisk (*) as in "DRMD*" indicates that the DRMD
signal goes on when '0'.
In practically all cases, the internal mechanisms of a microprocessor cannot be checked in the field. Therefore, the operations
of the microprocessors used in the machines are not discussed: they are explained in terms of from sensors to the input of
the DC controller PCB and from the output of the DC controller PCB to the loads.
The descriptions in this Service Manual are subject to change without notice for product improvement or other purposes, and
major changes will be communicated in the form of Service Information bulletins.
All service persons are expected to have a good understanding of the contents of this Service Manual and all relevant Service
Information bulletins and be able to identify and isolate faults in the machine.
Important Notices