WG82574L S LBA8 Intel, WG82574L S LBA8 Datasheet - Page 199

• Manufacturer Part Number: WG82574L S LBA8
• Manufacturer: Intel

Specifications of WG82574L S LBA8

• Operating Supply Voltage (typ): 3.3V
• Operating Temp Range: 0C to 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 64
• Lead Free Status / RoHS Status: Compliant

System Manageability—82574 GbE Controller
Table 52.
8.4.4.1
8.4.4.2
Note:
8.4.4.3
Note:
S
P
PEC
A
N
Rd
Wr
Field Name
Shorthand Field Name
SMBus Addressing
The SMBus addresses (enabled from the NVM) can be re-assigned using the SMBus
ARP protocol.
In addition to the SMBus address values, all parameters of the SMBus (SMBus channel
selection, address mode, and address enable) can be set only through NVM
configuration. Note that the NVM is read at the 82574’s power up and resets.
All SMBus addresses should be in Network Byte Order (NBO); MSB first.
SMBus ARP Functionality
The 82574 supports the SMBus ARP protocol as defined in the SMBus 2.0 specification.
The 82574 is a persistent slave address device so its SMBus address is valid after
power-up and loaded from the NVM. The 82574 supports all SMBus ARP commands
defined in the SMBus specification both general and directed.
The SMBus ARP capability can be disabled through the NVM.
SMBus ARP Flow
SMBus ARP flow is based on the status of two flags:
These flags are internal 82574 flags and are not exposed to external SMBus devices.
Since the 82574 is a Persistent SMBus Address (PSA) device, the AV flag is always set,
while the AR flag is cleared after power up until the SMBus ARP process completes.
Since AV is always set, the 82574 always has a valid SMBus address.
When the SMBus master needs to start an SMBus ARP process, it resets (in terms of
ARP functionality) all devices on the SMBus by issuing either Prepare to ARP or Reset
Device commands. When the 82574 accepts one of these commands, it clears its AR
flag (if set from previous SMBus ARP process), but not its AV flag (The current SMBus
address remains valid until the end of the SMBus ARP process).
SMBus START Symbol
SMBus STOP Symbol
Packet Error Code
ACK (Acknowledge)
NACK (Not Acknowledge)
Read Operation (Read Value = 1b)
Write Operation (Write Value = 0b)
• AV (Address Valid): This flag is set when the 82574 has a valid SMBus address.
• AR (Address Resolved): This flag is set when the 82574 SMBus address is resolved
(SMBus address was assigned by the SMBus ARP process).
Definition
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