SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
The video port pixel clock (VP_PCLK) is generated from the functional clock (CAL_FCLK). Software sets the peak pixel rate using the CAL_VPORT_CTRL1[16:0] PCLK register bit-field. The pixel rate is automatically controlled by the hardware, when data arrives from the RD_DMA.
The mean pixel clock rate on the video port can be given with the equation:
VP_PCLK = CAL_FCLK × CAL_VPORT_CTRL1[16:0] PCLK / 65536
As VP_PCLK is generated from the CAL functional clock, some clock pulses are gated to reach the selected frequency. The following algorithm is used to generate the internal PCLK_EN signal:
The configured pixel clock is used for active as well as for blanking periods.