ePCI-X Bus Details

6

ePCI-X Bus Details

6.1NuPRO-850 ePCI-X Bus

The NuPRO-850 provides PCI-X/PCI buses. Bus-A can run up to 64-bit PCI-X 66. Bus-B can run PCI 33MHz.

The ePCI-X Bus pin assignment is compatible with the PICMG 1.2 ePCI-X specifications. In the following sections, we will describe the detail signal definition and the design guide for the backplane designer to be compatible with the NuPRO-850 ePCI-X bus.

6.2Global Signals

6.2.1Standby Supply (+3.3Vaux)

The NuPRO-850 onboard circuit generate 3.3Vaux power from the +5Vaux or +5V. Therefore, NuPRO-850 does not require the backplane to provide +3.3Vaux.

6.2.2ATX Support

The ATX support signals include PWRGD, PSON#, PWRBT#, +5Vaux. The NuPRO-850 design provides the ATX power control capability.

If the backplane did not provide the +5Vaux, then the PWRBT# and PSON# will not work under ATX power mode. Users have to setup the external wiring to switch on/off the power supply.

6.2.3JTAG

NuPRO-850 does NOT implement the JTAG signals.

6.2.4I2C Bus

The onboard SMBus is connected to the SER_SCL and SER_SDA pins.

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Intel user manual ePCI-X Bus Details, NuPRO-850 ePCI-X Bus, Global Signals, Standby Supply +3.3Vaux, ATX Support, Jtag