Emerson RTM-ATCA-F140, Installation And Use Manual

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Functional Description
RTM-ATCA-F140 Installation and Use (6806800M97A)
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4.4.1 Connectivity
The two 10Gbps XAUI ports from the front blade base switch connect to a BCM8727 dual
XAUI-to-SFI PHY which then connect to two individual SFP+ connectors using an SFI interface
as shown in
Figure 4-3 . The RTM-ATCA-F140 includes 0.1 μ F AC-coupling capacitors on the XAUI
inputs from the front blade. Similarly, capacitors are expected to be provided on the front
blade for signals from the RTM. The SFP+ specification requires AC-coupling capacitors in the
module so they are not needed on the board SFI interface.
4.4.2 Front-Blade Port Mapping
The two base channel ports connect to the front blade ports BIX_XG0 and BIX_XG1. These
ports connect directly to dedicated ports on the ATCA-F140 front blade base switch. BIX_XG0
is connected to BCM8727 channel 2 while BIX_XG1 is connected to BCM8727 channel 1.
4.4.3 BCM8727 Configuration Flash
The BCM8727 requires an external SPI Flash to store microcode for the internal microcontroller.
A single SPI Flash is connected to the FPGA and the SPI bus from the BCM8727 is similarly
connected to the FPGA. Register settings in the FPGA allow the BCM8727 to connect to the SPI
Flash as well as provide a programming port.
4.4.4 Transmitter Control
The TXONOFF signals on the BCM8727 are individually connected to the RTM FPGA which
allows them to be driven under software control. This enables software to enable and disable
the SFP+ optical outputs.
Figure 4-3 Fabric 10 GB Interconnect
DUAL PHY
BCM8727
2x SFP+
2x SFI 2x 10GbE to Base Switch (XAUI)
Front Panel
Base Switch
Zone 3 Connector
EA Version