USB2640I Standard Microsystems Corp., USB2640I Datasheet - Page 27

• Manufacturer Part Number: USB2640I
• Description: Industrial Temperature Usb 2.0 Flash Media Controller And Usb Hub Combo
• Manufacturer: Standard Microsystems Corp.

Industrial Temperature USB 2.0 Flash Media Controller and USB Hub Combo
Chapter 7 Configuration Options
SMSC USB2640i/USB2641i
7.1
7.1.1
7.1.1.1
7.1.2
7.2
7.3
7.3.1
SMSC’s USB 2.0 hub is fully compliant to the Universal Serial Bus Specification available from the
USB Implementer’s Forum found at http://www.usb.org (Revision 2.0 April 27, 2000 and the 12/7/2000
and 5/28/2002 Errata) . Please reference Chapter 11 (Hub Specification) for general details regarding
hub operation and functionality.
The hub provides 1 transaction translator (TT) that is shared by both downstream ports (defined as
single-TT configuration). The TT contains 4 non-periodic buffers.
Hub Configuration Options
The SMSC hub supports a large number of features (some are mutually exclusive), and must be
configured in order to correctly function when attached to a USB host controller. There are two principal
ways to configure the hub; The internal default settings or by settings stored in an external EEPROM
or SPI Flash device.
Power Switching Polarity
The hub only supports “active high” port power controllers.
VBus Detect
According to Section 7.2.1 of the USB 2.0 Specification, a downstream port can never provide power
to its D+ or D- pull-up resistors unless the upstream port’s VBUS is in the asserted (powered) state.
The VBUS_DET pin on the hub monitors the state of the upstream VBUS signal and will not pull-up
the D+ resistor if VBUS is not active. If VBUS goes from an active to an inactive state (Not Powered),
the hub will remove power from the D+ pull-up resistor within 10 seconds.
The SMSC USB2640i/USB2641i is fully compliant with the following flash media card reader
specifications:
EEPROM/SPI Interface
The USB2640i/USB2641i can be configured via a 2-wire (I
flash device containing the firmware for the USB2640i/USB2641i. If an external configuration device
does not exist the internal default values will be used. If one of the external devices is used for
Hub
Card Reader
System Configurations
Memory Stick Specification 1.43
Memory Stick Pro Format Specification 1.02
Memory Stick Pro-HG Duo Format Specification 1.01
-Memory Stick, MS Duo, HS-MS, MS Pro-HG, MS Pro
xD-Picture Card 1.2 compliant
Secure Digital 2.0 / MultiMediaCard Specification 4.3
-SD 2.0, HS-SD, HC-SD
-TransFlash™ and reduced form factor media
-1/4/8 bit MMC 4.2
DATASHEET
27
2
C) EEPROM (256x8) or an external SPI
Revision 2.0 (10-03-08)