Basic Sequence of Operation The Formatter PCA and the Engine Controller Board share information during printer operation. The Interface PCA forms a link which operates as a serial data bus. This allows printer status, command, and dot-image data to be passed between the two PCAs. Table 5-1 shows the general timing of the printer events. The following events take place during normal printer operation: Table 5-1. Printer Timing Period Timing Purpose WAIT From power on to the end of Main Motor initial rotation. Clears the Drum surface potential and cleans the Transfer Roller. STBY (standby) From the end of the WAIT or the LSTR period until the input of the PRNT signal from the Formatter.
Or from the end of the LSTR period until power off. Maintains the printer in ready state. INTR (initial rotation) From the input of the PRNT signal from the Formatter until the Engine Controller outputs the TOP signal. Stabilizes the photosensitive Drum sensitivity in preparation for printing. Also cleans the Transfer Roller. PRNT After the end of initial rotation until the top of the page sensor detects the trailing edge of the paper. Forms images on the photosensitive Drum based on the /VDO signal from the Formatter and transfers the image to paper. LSTR (last rotation) From the primary voltage (DC) off until the main motor stops.
Delivers the last sheet of paper and cleans the Transfer Roller. If another PRNT signal is sent from the Formatter, the printer returns to the INTR period. If not, it returns to the STBY period. Basic Sequence of Operation 5-49