SMSC USB2507 manual 12

							Integrated USB 2.0 Compatible 7-Port Hub
							Datasheet
		Table 4.1 7-Port Hub Pin Descriptions (continued)
NAME		SYMBOL		TYPE			FUNCTION
				SERIAL PORT INTERFACE
Serial Data/SMB		SDA/SMBDATA		IOSD12		(Serial Data)/(SMB Data) signal.
Data
Serial Clock/SMB		SCL/SMBCLK/		IOSD12		(Serial Clock)/(SMB Clock) signal. This multifunction pin is
Clock		CFG_SEL0				read on the rising edge of RESET_N (see the applicable
&						RESET_N timing table in Section 5.6.1) and will determine
Config Select 0						the hub configuration method as described in Table 4.2.
Configuration		CFG_SEL1		I		This multifunction pin is read on the rising edge of
Programming						RESET_N (see the applicable RESET_N timing table in
Select						Section 5.6.1) and will determine the hub configuration
						method as described in Table 4.2.
		Table 4.2 SMBus or EEPROM Interface Behavior
	CFG_SEL1		CFG_SEL0		SMBus or EEPROM interface behavior.
	0			0	Reserved
	0			1	Configured as an SMBus slave for external download of user-
					defined descriptors. SMBus slave address is 0101100
	1			0	Internal Default Configuration via strapping options.
	1			1	2-wire (I2C) EEPROMS are supported,
				Table 4.3 Miscellaneous Pins
NAME		SYMBOL		TYPE			FUNCTION
Crystal		XTAL1/		ICLKx			24MHz crystal or external clock input.
Input/External		CLKIN					This pin connects to either one terminal of the crystal or
Clock Input							to an external 24MHz clock when a crystal is not used.
Crystal Output		XTAL2		OCLKx			24MHz Crystal
							This is the other terminal of the crystal, or left
							unconnected when an external clock source is used to
							drive XTAL1/CLKIN. It must not be used to drive any
							external circuitry other than the crystal circuit.
Clock Input		CLKIN_EN		I			Clock In Enable:
Enable							Low = XTAL1 and XTAL2 pins configured for use with
							external crystal
							High = XTAL1 pin configured as CLKIN, and must be
							driven by an external CMOS clock.
RESET Input		RESET_N		IS			This active low signal is used by the system to reset the
							chip. The minimum active low pulse is 1us.
Self-Power /		SELF_PWR		I			Detects availability of local self-power source.
Bus-Power							Low = Self/local power source is NOT available (i.e., Hub
Detect							gets all power from Upstream USB VBus).
							High = Self/local power source is available.
TEST Pins		TEST[1:0]		IPD			Used for testing the chip. User must treat as a no-
							connect or connect to ground.

Revision 2.3 (08-27-07)	12	SMSC USB2507
	DATASHEET