SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
As shown in Figure 9-169, the VDINT0, VDINT1, and VDINT2 interrupts occur relative to the VD pulse. The trigger timing is selected by using the ISIF_MODESET[2] VDPOL bit setting. VDINT0, VDINT1, and VDINT2 occur after receiving the number of horizontal lines (HD pulse signals) set in the ISIF_VDINT0[14:0] CDV0, ISIF_VDINT1[14:0] CDV1, and ISIF_VDINT2[14:0] CDV2 register fields, respectively.
In the case of BT.656 input mode, there is a VD at the beginning of each field. Therefore, there are two interrupts for each frame (that is, one for each field).
If the ISIF_MODESET[2] VDPOL bit is set to 0, the VDINT0, VDINT1, and VDINT2 HD counters begin counting HD pulses from the rising edge of the external VD.
If the ISIF_MODESET[2] VDPOL bit is set to 1, the VDINT0, VDINT1, and VDINT2 HD counters begin counting HD pulses from the falling edge of the external VD.