Ampro Corporation COM 830 Tvdacb, Tvdacc, I2CCK, I2CDAT, Spkr, Speaker, Biosdisable, Wdt, Kbdrst#

Chapter 3					Signals and Pinout Tables
Table 3-11. TV-Out Signal Descriptions (Continued)
	TV_DAC_B	TVDAC Channel B Output supports the	O		PD 150R		Analog
		following: Composite video: not used	Analog				output
		Component video: Luminance (Y) analog
		signal.
		S-Video: Luminance analog signal.
	TV_DAC_C	TVDAC Channel C Output supports the	O		PD 150R		Analog
		following: Composite video: not used	Analog				output
		Component: Chrominance (Pr) analog
		signal.
		S-Video: Chrominance analog signal.
Table 3-12. Miscellaneous Signal Descriptions
	Signal	Description		I/O	PU/PD	Comment
	I2C_CK	General purpose I²C port clock output		O 3.3V	PU 4k7
					3.3V
	I2C_DAT	General purpose I²C port data I/O line		I/O	PU 4k7
				3.3V	3.3V
	SPKR	Output for audio enunciator, the "speaker" in		O 3.3V		SPEAKER
		PC-AT systems				is a boot
						strap signal
						(see note 1
						below)
	BIOS_DISABLE	Module BIOS disable input. Pull low to disable		I 3.3V	PU 4k7
	#	module BIOS. Used to allow off-module BIOS			3.3V
		implementations.
	WDT	Output indicating that a watchdog time-out		I 3.3V	PU 10k	This signal
		event has occurred.			3.3V	is not
						supported
						(see note 2
						below)
	KBD_RST#	Input to module from (optional) external		I	PU 10k
		keyboard controller that can force a reset.			3.3V
		Pulled high on the module. This is a legacy
		artifact of the PC-AT.
	KBD_A20GATE	Input to module from (optional) external		I	PU 10k
		keyboard controller that can be used to control			3.3V
		the CPU A20 gate line. The A20GATE restricts
		the memory access to the bottom megabyte and
		is a legacy artifact of the PC-AT. Pulled low on
		the module.

NOTE Some signals have special functionality during the reset process. They may bootstrap some basic important functions of the module.

For more information about this signal, please visit Ask an Expert on the Ampro web site.

COM 830 Reference Manual 33