LAN9312 datasheet(37/458 Pages) SMSC

37 / 458 page

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

Datasheet

SMSC LAN9312

Revision 1.2 (04-08-08)

DATASHEET

Note 4.1

In the case of a soft reset, the EEPROM Loader is run, but loads only the MAC address

into the Host MAC. No other values are loaded by the EEPROM Loader in this case.

4.2.1

Chip-Level Resets

A chip-level reset event activates all internal resets, effectively resetting the entire LAN9312.

Configuration straps are latched, and the EEPROM Loader is run as a result of chip-level resets. A

chip-level reset is initiated by assertion of any of the following input events:

Power-On Reset (POR)

nRST Pin Reset

Chip-level reset completion/configuration can be determined by polling the READY bit of the Hardware

Configuration Register (HW_CFG) or Power Management Control Register (PMT_CTRL) until it is set.

When set, the READY bit indicates that the reset has completed and the device is ready to be

accessed.

With the exception of the Hardware Configuration Register (HW_CFG), Power Management Control

(RESET_CTL), read access to any internal resources is forbidden while the READY bit is cleared.

Writes to any address are invalid until the READY bit is set.

Note: The LAN9312 must be read at least once after any chip-level reset to ensure that write

operations function properly.

4.2.1.1

Power-On Reset (POR)

A power-on reset occurs whenever power is initially applied to the LAN9312, or if the power is removed

and reapplied to the LAN9312. This event resets all circuitry within the device. Configuration straps

are latched, and the EEPROM Loader is run as a result of this reset.

Table 4.1 Reset Sources and Affected LAN9312 Circuitry

RESET SOURCE

POR

XXXX

XXXXX

nRST Pin

XXXX

XXXXX

Digital Reset

XXX

XXXXX

Soft Reset

Note 4.1

Port 2 PHY

Port 1 PHY

Virtual PHY

LAN9312 Datasheet(PDF) 37 Page - SMSC Corporation

LAN9312 Datasheet(HTML) 37 Page - SMSC Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL