Projector Service Manual

Chapter 2—Functional Description
Model 330, 340SC and 370SC Service Manual 2-67
Table 2-12
System Controller Board I/O Signals
Video Processor Board
I/O Description
IICDATA Data line for transferring the following information
(I = input, O = output). The input data are associated with an
interrupt pulse.
I VIDOK
I SWEEPOK
I BEAMDET
O BENABLE
O GENABLE
O RENABLE
OCH1SEL
OCH2SEL
O SLOAD
O VERTICAL FREQUENCY
Input Description
/IICINT Interrupt used to tell the SCB that the VPB has data to report.
Video Processor Board
Output Description
IICCLK Clock signal for IIC data bus.
+SERCLK Serial data transfer clock.
-SERCLK Serial data transfer clock.
+SERDATA Serial data transfer. Used to transfer the following command data:
REDBIAS, GRNBIAS, and BLUBIAS to control the bias on
the three (3) ILA®s respectively, RCONT, GCONT, and
BCONT to control the contrast for the three CRTs, and
BRIGHT to control the brightness for all three CRTs.
-SERDATA Serial data transfer.
BONSCRN Output from the overlay interface used to turn blue overlay on and
off.
RONSCRN Similar to BONSCRN.
GONSCRN Similar to BONSCRN.
VONSCRN Output from overlay interface used to turn external video on and
off.
VIDTEST Video signal output for gray-scale. Real time data at 0V to 1V.
RSENS Sensitivity output from the DAC at 0V to 1V with 140 ohm Zout.
GSENS Similar to RSENS.
BSENS Similar to RSENS.
RTHRESH Threshold output from the DAC at 0V to 1V with 140 ohm .
GTHRESH Similar to RTHRESH.
BTHRESH Similar to RTHRESH.