SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
Three PLLs (PLL16, PLL17, and PLL19) are allocated to the DSS for sourcing the pixel clocks (dpi_[3:0]_in_clk.) (See clocking chapter for details.) PLL16/PLL17 should be the primary high-resolution display pclk sources (e.g. enabling 2.5K or 4K display output). PLL19 is associated closely with the DPI0 port. When dpi_1 or dpi_3 is selected to drive the DPI0 port, the dpi_0/3_in_clk must be sourced from this PLL. When DPI0 is not enabled, PLL19 can be used to source the pixel clock of other display outputs.
The PLL19 clock source can alternatively be driven by an external pixel clock input pin. This allows the DSS DPI output to be generated in genlock with an external clock source. The external pixel clock source for PLL19 HSDIV0_CLKOUT is selected by setting MMR_CTRL0 DPI0_CLK_CTRL[EXT_CLKSEL]=1.