All secondary data packets (SDP) are provided to the SN65DSI86 through the DSI interface during vertical blanking periods. (SDP are not supported using the I²C interface.) The SN65DSI86 will wrap the SDP provided to the DSI interface with the SS and SE control symbols and then transmit over the DP interface during the vertical blanking period. Secondary data packets are used to pass non-active video data to the eDP sink. Information like stereo video attributes and/or PSR-state data is sent using SDP. When SDP is used for stereo video attributes, software must program the MSA_MISC1_2_1 register with a zero.

The SN65DSI86 requires that the SDP be provided to the DSI interface in the following order:

1. 4 Bytes of Header (HB0 through HB3)
2. 4 Bytes of Header parity (PB0 through PB3)
3. 8 Bytes of Data (DB0 through DB7)
4. 2 Bytes of Data parity (PB4 and PB5)
5. 8 Bytes of Data (DB8 through DB15)
6. 2 Bytes of Data parity (PB6 and PB7)

For data payloads greater than 16 bytes, data must be provided in multiples of 8 bytes with of 2 bytes of parity. If the final multiple is less than 8, zero padding must be used to fill the remaining data positions.