Tektronix PHASER 380, Service Manual

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Service Manual 1-7
General Information
1
An internal data bus, called the I
2
C bus, connects all I/O boards to the main
board (through the power control 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 dozens of sensors and actuating
solenoids.
Figure 1-5 The printer’s I
2
C bus
I
2
C bus
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