SPRABA5D January 2014 – January 2019 AM1802 , AM1802 , AM1806 , AM1806 , AM1808 , AM1808 , AM1810 , AM1810
When the device is taken out of reset, the PLL modules are set in bypass mode by default. During application development, the PLL configuration is typically handled by a GEL file. In a production environment, the bootloader can configure the PLL. The AISgen General tab specifies the clock source and its frequency, and the PLL0 and PLL1 tabs can configure the multipliers and dividers to reach the desired CPU frequency.
The PLL0 tab appears when the Configure PLL0 checkbox is selected. This tab configures the multiplier and dividers for PLL0. When changing any of these values, calculated frequencies will update to reflect the changes. The multiplier and divider values that you enter are the actual multiplication and division factors (x), not the values that get programmed into the corresponding PLL registers (x - 1). The default settings of the PLL dividers that are not configurable are shown in Table 5.
Divider | Configured To |
---|---|
PLL0 DIV2 | Divide by 2 |
PLL0 DIV4 | Divide by 4 |
PLL0 DIV6 | Divide by 1 |
The PLL1 tab appears when the Configure PLL1 checkbox is selected. Note that PLL1 must be configured if DDR is configured. Selecting the Configure DDR checkbox will automatically select Configure PLL1 as well. This tab is similar to the PLL0 tab, but its settings are applied to PLL1 instead of PLL0.