JVC 330, 370 SC, 340 SC service manual Horizontal Deflection Board I/O

Chapter 2—Functional Descriptions

Bus	I/O	Information	Description
IIC	I	Serial data load	Command to the serial data receiver that the
			incoming data is to be read.
Serial	I	HPHASE	Commanded horizontal phase of picture.
Serial	I	HLINR	Commanded amount of overall H linearity
			correction.
Serial	I	TBKEY	Commanded amount of top and bottom Keystone
			Correction.
Serial	I	HCENTBLU	Commanded horizontal position of blue raster.
Serial	I	HCENTGRN	Commanded horizontal position of green raster.
Serial	I	HCENTRED	Commanded horizontal position of red raster
Serial	I	WIDTH	Commanded width of raster

Horizontal Deflection Board I/O

This section provides a description of the inputs to and outputs from the HDB. The I/O description are arranged by the source/destination of the signal and so the assemblies communicated with are used as the primary heading of each group of signals and then are further subdivided into inputs and outputs. In each case, the signal's direction is noted, with input referring to an input to the RTG, and output to an output from the HDB. (e.g.: under Raster Timing Generator 'Input'; /VFBST refers to the signal /VFBST that is an input to the HDB from the Raster Timing Generator). When test points are provided for the I/O they are noted.

Table 2-7Horizontal Deflection Board I/O Signals

	System Controller Board
Inputs	Description
IICCLK	IIC clock line. Unidirectional clock line for control of synchronous data
	transfer over IIC data bus.
+SERCLK	Serial data transfer clock (+). Unidirectional, differential clock line from
	SCB to other circuit boards. Used for synchronous control of serial
	communication over SERDATA data lines.
-SERCLK	Serial data transfer clock (-).
	System Controller Board
Inputs	Description
+SERDATA	Serial data transfer. Unidirectional, differential, synchronous serial data
	communication line. Used for transferring data from SCB to other
	circuit boards. Uses SERCLK and IIC for control of receiver.
-SERDATA	Serial data transfer
Outputs	Description
/IICINT	IIC interrupt line. Signal line for slave boards to inform the SCB (master)
	that there is data to be transferred. Master then polls slaves to
	determine the source of the interrupt.
I/O	Description

2-30 Model 330. 340SC, and 370SC Service Manual