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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The conversion process depends on which input frequency is in use. Figure 4-6Synchronous
Ethernet Reference Recovery shows the process. A register setting for each of the two reference
outputs selects between the two input frequencies.
4.8.8 SPI Flash
The SPI ports from the BCM8727, BCM84754, and BCM84740 connect to the FPGA along with
three SPI Flash devices, one for each type. Register settings allow access to be granted to any of
the PHYs and also provide a programming port.
4.8.9 FPGA Register Map
Details of the FPGA register map are included in the RTM FPGA section of the ATCA-F140 FPGA
design guide.
Figure 4-6 Synchronous Ethernet Reference Recovery
Digital
Frequency
Synthesizer
x32
Synchronous
Divider
/25
Synchronous
Divider
/25782 ,
25781 , 25781 ,
25781
(25781 .25
overall)
161.1328125 MHz
8 kHz
Synchronous
Divider
/19532 ,
19531 , 19531 ,
19531
(19531 .25
overall)
156.25 MHz
EA Version