SNLS589B September 2016 – July 2018 DS90UB960-Q1
In External FrameSync mode, an external signal is input to the DS90UB960-Q1 through one of the GPIO pins on the device. The external FrameSync signal may be propagated to one or more of the attached FPD3 Serializers through a GPIO signal in the back channel.
Enabling the external FrameSync mode is done by setting the FS_MODE control in the FS_CTL register to a value between 0x8 (GPIO0 pin) to 0xF (GPIO7 pin). Set FS_GEN_ENABLE to 0 for this mode.
To send the FrameSync signal on a port’s BC_GPIOx signal, the BC_GPIO_CTL0 or BC_GPIO_CTL1 register should be programmed for that port to select the FrameSync signal.