IDT EB-LOGAN-23, Руководство пользователя

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IDT Installation of the EB-LOGAN-23 Evaluation Board
89EB-LOGAN-23 Evaluation Board 2 - 6 February 16, 2011
Notes .
The frequency of the global reference clock input may be selected by the Clock Frequency Select
(GCLKFEL) pin to be either 100 MHz or 125 MHz as described in Table 2.3.
The source for the onboard clock is the ICS841484 clock generator device (U49) connected to a 25MHz
oscillator (X1). When using the onboard clock generator, the output frequency can be selected using
ICS_FS (SW10, bit 1). The default setting is ON. See Table 2.4.
The output of the onboard clock generator is accessible through SMA or SATA connectors. See Table
2.5. This can be used to connect a scope for probing or capturing purposes and cannot be used to drive the
clock from an external source.
Local Port Input Clocks
Associated with some ports is a local port reference clock input (PxCLK). Detailed information on the
concept behind local port clocking features are described in the Device User Manuals. Depending on the
port clocking mode, a differential reference clock can be driven into the device on the corresponding
PxCLKP and PxCLKN pins. The frequency of a port reference clock input is always 100 MHz. Table 2.6 lists
the possible sources for the port reference clock input, and Table 2.7 lists the possible sources for the slot
clock input.
Jumper Selection
J6 [1-3 / 2-4] SMA (J5/J7)
[5-7 / 6-8] Onboard Clock Generator (U49)
[7-9 / 8-10] SATA (J8) (default)
Table 2.2 Clock Buffer Input Sources
Global Clock Frequency Switch - SW10[2]
SW10[2] Clock Frequency
ON 100 MHz (Default)
OFF 125 MHz
Table 2.3 Global Reference Input Clock Frequency Select
Onboard Clock Frequency Switch - SW10[1]
SW10[1] Clock Frequency
ON 100 MHz (Default)
OFF 125 MHz
Table 2.4 Onboard Clock Generator Frequency Select
Onboard Reference Clock Output (Differential)
TP119 Positive Reference Clock
TP120 Negative Reference Clock
J121 SATA Reference Clock
Table 2.5 Onboard Reference Clock Generator Access Points