JVC 340 SC, 330, 370 SC service manual Raster Timing Generator I/O, Iicclk

		Chapter 2—Functional Description
I	T Blank	Commanded position of top blanking.
I	B Blank	Commanded position of bottom blanking.
I	/STBP	Command for DC restore timing on either
		leading or trailing edge of sync pulse.
I	DC Restore Delay	Commanded timing of DC restore after
		reference edge of sync pulse.
I	Internal Sync Forced	Command to force internal sync select.
I	Correction Start Delay	Commanded H phase of correction map.
I	Pincushion Start Delay	Commanded H phase of pincushion, keystone,
		and linearity correction.
I	2H Sync Enable	Command determines path of H sync signal.
I	Shifted Sync Enable	Command determines path of H sync signal.
O	/External Sync Detect	Is an external sync available.
O	HCount	Count of H lines per frame.
O	/Phase Lock	Indication of PLL lock.
O	Phase Count	Indication of phase difference between
		HSYNC and HFlyback.

Raster Timing Generator I/O

This section provides a description of the inputs to and outputs from the RTG. 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 RTG. (e.g.: under System Controller Board “Input”; SYSCLK refers to the signal SYSCLK that is an input to the RTG from the System Controller Board). When test points are provided for the I/O they are noted.

Table 2-5Raster Timing Generator I/O Signals

	System Controller Board
Inputs	Description
SYSCLK	4 MHz clock signal for derivation of internal HDTV sync signal.
	(TP 13)
IICCLK	IIC clock line. Unidirectional clock line for control of
	synchronous data transfer over IIC data bus.

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.
/Hx224	Square wave signal 224 X the horizontal frequency for overlay
	address generator clocking. (TP 23)

Model 330, 340SC and 370SC Service Manual 2-23