ADLINK Technology CoreModule 745, Reference Manual

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Chapter 3 Hardware
CoreModule 745 Reference Manual 31
Table 3-13 describes the pin signals of the Utility interface, which uses a 5-pin, single-row header with
0.100" (2.54mm) pitch.
Note: The shaded table cells denote power or ground. The * symbol indicates the signal is Active Low.
System Management Bus (SMBus)
The ICH8-M chip contains a host SMBus port. The host port allows the CPU access to the SMBus slaves
through header, J20. The SMBus slaves include the SODIMM EPROM, Clock Buffer, Clock Generator, and
the Gb Ethernet Controller. Table 3-14 lists the device names and corresponding reserved binary addresses
on the SMBus. Table 3-15 lists the SMBus pin signals, which are routed through a 5-pin, single-row header
with 0.049" (2 mm) pitch.
Note: The shaded table cells denote power or ground. The * symbol indicates the signal is Active Low.
System Fan
Table 3-16 lists the pin signals of the optional System Fan header, which provides 3 pins with 0.079" (2mm)
pitch.
Note: The shaded table cells denote power or ground.
Table 3-13. Utility Interface Pin Signals (J23)
Pin # Signal Description
1 /PWR_BTN* External Power Button (Pins 1-2)
2 GND Ground
3 /RESET SW* External Reset Switch signal (Pins 2-3)
4 5V +5 Volts Power
5 SPKR_CONN Speaker Output (Pins 4-5)
Table 3-14. SMBus Reserved Addresses
Component Address Binary
SODIMM EPROM 1010,000x
b
Clock Generator 1101,001x
b
Clock Buffer 1101,110x
b
Gb Ethernet Controller 1100,001x
b
Table 3-15. SMBus Pin Signals (J20)
Pin # Signal Description
1 SMB_CLK SMBus Clock
2 GND Ground
3 SMB_DATA SMBus Data
4 VSM +3.3V standby voltage
5 /SMB_ALERT* SMBus Alert
Table 3-16. Optional System Fan Pin Signals (J22)
Pin # Signal Description
1 VCC +5.0 volts DC +/- 5%
2 NC Not Connected
3 GND Ground