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Service Guide
9
An internal data bus, called the I
2
C bus, connects all I/O boards to the main
board. Through this single bus, the main board can “poll” the I/O boards for the
state of the printer’s sensors as well as actuate the printer’s solenoids. This data
bus greatly simplifies the wiring that would otherwise be required for monitoring
numerous sensors and solenoids. The I
2
C bus also extends down to the High-
capacity Paper Trays.
The printer’s I
2
C bus
0388-05
I
2
C bus
High capacity
Paper Tray
connection
Summary of Contents for Phaser 840
Page 46: ...36 Phaser 840 Color Printer ...
Page 95: ...Service Guide 85 Clearing PostScript NVRAM menu item ...
Page 96: ...86 Phaser 840 Color Printer ...
Page 121: ...Service Guide 111 Figure 1 Cabinet FRUs 7 5 6 8 1 2 4 0388 21 3 ...
Page 125: ...Service Guide 115 Figure 3 Paper path FRUs 0388 16 2 1 5 11 10 9 12 6 4 3 7 13 8 ...
Page 127: ...Service Guide 117 Figure 4 Motors and fans FRUs 0388 14 7 4 3 5 6 2 1 ...
Page 129: ...Service Guide 119 Figure 5 Circuit boards FRUs 4 3 5 2 1 9 7 6 8 10 11 13 0388 13 12 ...
Page 131: ...Service Guide 121 Figure 6 Solenoids and clutches FRUs 4 5 3 2 1 0388 23 ...
Page 137: ...Service Guide 127 Figure 9 High capacity PaperTray 0388 65a 1 2 ...
Page 142: ...132 Phaser 840 Color Printer ...
Page 154: ...144 Phaser 840 Color Printer ...