The QPLL VCOs have different operating bands, see the device specific data sheet for more information.
The frequency out of the PLL is given by:
Where N = QPLL(0/1)_FBDIV and M = QPLL(0/1)_REFCLK_DIV.
Note: For GTH, FractionalPart=1 and QPLL_CLKOUTRATE=2
To calculate the line rate use:
Where D = (R/T)XOUT_DIV.
|
Factor |
Attribute |
Valid Settings |
|---|---|---|
|
M |
QPLL0_REFCLK_DIV QPLL1_REFCLK_DIV |
1, 2, 3, 4 |
|
N |
QPLL0_FBDIV QPLL1_FBDIV |
16, 20, 32, 40, 64, 66, 80, 100 |
|
D |
RXOUT_DIV TXOUT_DIV |
1, 2, 4, 8, 16 |
The following table shows addresses of interest as well as the bits and encoding that must be used to select the correct divider values when interpreting the register content.