Appendix C: Theory Of Operation; Por Sequence; Printer Control; Paper Path Information - Lexmark MS315 Service Manual

Appendix C: Theory of operation

POR sequence

At power on, the engine code goes through a series of tests to verify hardware integrity. If a hardware failure is detected,
it will be reported to the printer. If the POR sequence cannot be completed successfully, the printer may post an error
message identifying service may be needed.

Printer control

The printer uses a single processor for both RIP and engine functions. The raster image processor (RIP) code performs
system responsibilities such as PC connection, LAN, ISP attachments, and bitmap generation. The engine code performs
tasks related to the operation of the electrical and mechanical device systems such as motors, lasers, power supplies,
and fusers. The NVRAMs are located on the controller board and control panel, replacement of either the controller
board or control panel will pull or mirror NVRAM data from each other.

Paper path information

Input tray

When feeding media, the ACM lowers to come into contact with the media. The pick rollers on the ACM rotate to push
the media to the wear strips at the front of the tray. The wear strips provide a fixed resistance to ensure that sheets
are fed one at a time. The media is then fed to the secondary input roller and then to the first input roller.

Multipurpose feeder (MPF)

The driving force from the main drive motor is transmitted through the MPF gearbox. When the MPF solenoid activates,
it allows the MPF sector gear linked to the MPF gearbox to rotate. The MPF pick roll shaft is connected to the MPF
sector gear.
Appendix C: Theory of operation
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First input roller
Secondary input
roller
Wear strips
Pick rollers
Option tray
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