2 i2c eeprom, 3 in-circuit eeprom programming, In-circuit eeprom programming – SMSC USB2513 User Manual

Page 52: C eeprom

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USB 2.0 Hi-Speed Hub Controller

Datasheet

Revision 1.0 (3-11-09)

52

SMSC USB251x

DATASHEET

8.2.1.35

Register FFh: Status/Command

8.2.2

I

2

C EEPROM

The I

2

C EEPROM interface implements a subset of the I

2

C Master specification (Please refer to the

Philips Semiconductor Standard I

2

C-Bus specification for details on I

2

C bus protocols). The SMSC

hub’s I

2

C EEPROM interface is designed to attach to a single “dedicated” I

2

C EEPROM, and it

conforms to the Standard-mode I

2

C specification (100 kbit/s transfer rate and 7-bit addressing) for

protocol and electrical compatibility.

Note: Extensions to the I

2

C specification are not supported.

The hub acts as the master and generates the serial clock SCL, controls the bus access (determines
which device acts as the transmitter and which device acts as the receiver), and generates the START
and STOP conditions.

8.2.2.1

Implementation Characteristics

The hub will only access an EEPROM using the sequential read protocol.

8.2.2.2

Pull-Up Resistor

The circuit board designer is required to place external pull-up resistors (10 k

Ω recommended) on the

SDA / SMBDATA & SCL / SMBCLK / CFG_SEL[0] lines (per SMBus 1.0 specification, and EEPROM
manufacturer guidelines) to VDD33 in order to assure proper operation.

8.2.2.3

I

2

C EEPROM Slave Address

The slave address is 1010000.

Note: 10-bit addressing is NOT supported.

8.2.3

In-Circuit EEPROM Programming

The EEPROM can be programmed via ATE (automatic test equipment) by pulling RESET_N low
(which tri-states the hub’s EEPROM interface and allows an external source to program the EEPROM).

BIT

NUMBER

BIT NAME

DESCRIPTION

7:3

Reserved

Reserved

2

INTF_PW_DN

SMBus Interface Power Down

‘0’ = Interface is active

‘1’ = Interface power down after ACK has completed

1

RESET

Reset the SMBus Interface and internal memory back to RESET_N

assertion default settings.

‘0’ = Normal Run/Idle State

‘1’ = Force a reset of registers to their default state

0

USB_ATTACH

USB Attach (and write protect)

‘0’ = SMBus slave interface is active

‘1’ = The hub will signal a USB attach event to an upstream device, and the

internal memory (address range 00h-FEh) is “write-protected” to prevent

unintentional data corruption.

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