Intel Xeon E7430 AD80583QH046003 Data Sheet

Product codes
AD80583QH046003
Page of 136
Intel® Xeon® Processor 7400 Series Datasheet
111
Features
Note:
Actual implementation may vary. This figure is provided to offer a general understanding of the 
architecture. All SMBus pull-up and pull-down resistors are 10 kΩ and located on the processor.
7.4.1
SMBus Device Addressing
Of the addresses broadcast across the SMBus, the memory component claims those of 
the form “1010XXXZb”. The “XXX” bits are defined by pull-up and pull-down resistors 
on the system baseboard. These address pins are pulled down weakly (10 kΩ) on the 
processor substrate to ensure that the memory components are in a known state in 
systems which do not support the SMBus (or only support a partial implementation). 
The “Z” bit is the read/write bit for the serial bus transaction.
Note that addresses of the form “0000XXXXb” are Reserved and should not be 
generated by an SMBus master. The system designer must also ensure that their 
particular implementation does not add excessive capacitance to the address inputs. 
Excess capacitance at the address inputs may cause address recognition problems. 
Refer to the appropriate platform design guide document.
 shows a logical diagram of the pin connections. 
 describe the 
address pin connections and how they affect the addressing of the devices.
Figure 7-2. Logical Schematic of SMBus Circuitry
Processor 
Information 
ROM              
and Scratch 
EEPROM    
(1Kbit each)
VSS
SM_VCC
SM_EP_A0
SM_EP_A1
SM_EP_A2
SM_WP
SM_CLK
SM_DAT
VCC
CLK
DATA