USB2503 datasheet(33/46 Pages) SMSC

33 / 46 page

USB 2.0 High-Speed 4-Port Hub Controller

Datasheet

SMSC USB2514

Revision 1.92 (05-08-07)

DATASHEET

20 bytes to send, the first byte would be the number 20 (14h), followed by the 20 bytes of data. The

byte count may not be 0. A Block Read or Write is allowed to transfer a maximum of 32 data bytes.

Note: For the following SMBus tables:

Figure 4.1 Block Write

Block Read

A Block Read differs from a block write in that the repeated start condition exists to satisfy the I2C

specification’s requirement for a change in the transfer direction.

Figure 4.2 Block Read

4.4.2

Invalid Protocol Response Behavior

Registers that are accessed with an invalid protocol are not updated. A register is only updated

following a valid protocol. The only valid protocols are Write Block and Read Block, which are

described above.

The Hub only responds to the hardware selected Slave Address.

Attempting to communicate with the Hub over SMBus with an invalid slave address or invalid protocol

results in no response, and the SMBus Slave Interface returns to the idle state.

The only valid registers that are accessible by the SMBus slave address are the registers defined in

the Registers Section. See Section 4.4.3 for the response to undefined registers.

4.4.3

General Call Address Response

The Hub does not respond to a general call address of 0000_000b.

Denotes Master-to-Slave

Denotes Slave-to-Master

USB2503 データシート(PDF) 33 Page - SMSC Corporation