High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface

Datasheet

BITS

DESCRIPTION

TYPE

DEFAULT

 

 

 

 

19:16

TX FIFO Size (TX_FIF_SZ)

R/W

5h

 

This field sets the size of the TX FIFOs in 1KB values to a maximum of

 

 

 

14KB. The TX Status FIFO consumes 512 bytes of the space allocated by

 

 

 

TX_FIF_SIZ, and the TX Data FIFO consumes the remaining space

 

 

 

specified by TX_FIF_SZ. The minimum size of the TX FIFOs is 2KB (TX

 

 

 

Data FIFO and Status FIFO combined). The TX Data FIFO is used for both

 

 

 

TX data and TX commands.

 

 

 

The RX Status and Data FIFOs consume the remaining space, which is

 

 

 

equal to 16KB minus TX_FIF_SIZ. See section Section 9.7.3, "FIFO

 

 

 

Memory Allocation Configuration," on page 121 for more information.

 

 

 

 

 

 

15:14

RESERVED

RO

-

 

 

 

 

13:12

RESERVED - This field must be written with 00b for proper operation.

R/W

00b

 

 

 

 

11:1

RESERVED

RO

-

 

 

 

 

0

Soft Reset (SRST)

R/W

0b

 

Writing 1 generates a software initiated reset to the Host Bus Interface, the

SC

 

 

Host MAC, and System CSR’s below address 100h. The System CSR’s are

 

 

 

all reset except for any NASR bits. Soft reset also clears any TX or RX

 

 

 

errors in the Host MAC transmitter and receiver (TXE/RXE). This bit is self-

 

 

 

clearing. In order to reset all values, the Reset Control Register

 

 

 

(RESET_CTL) must be used.

 

 

 

Note: This bit will read high during assertion of DIGITAL_RST in the

 

 

 

Reset Control Register (RESET_CTL). The LAN9312 must always

 

 

 

be read at least once after power-up or reset to ensure that write

 

 

 

operations function correctly.

 

 

 

 

 

 

Note 14.47 The default value of this field is determined by the configuration strap auto_mdix_strap_2. See Section 4.2.4, "Configuration Straps," on page 40 for more information.

Note 14.48 The default value of this field is determined by the configuration strap auto_mdix_strap_1. See Section 4.2.4, "Configuration Straps," on page 40 for more information.

Revision 1.4 (08-19-08)

262

SMSC LAN9312

 

DATASHEET