Q: Please provide some guidance for required register write sequencing in ADV7850. This is not all clear in the Recommended Settings document.
A: I2C sequencing in our scripts associated with the evaluation board is generally the best guideline.
ADI's scripts are generally initiated following a reset, so complex configuration changes on the fly that do not utililize a reset are generally more susceptible to possible issues.
Some sequencing should be inferred as required - e.g. the I2C addresses for programmable-address register maps need to be programmed (in the main map) before those I2C maps are written to.
For ADV7850 in particular, the analog front end/HDMI Rx is normally programmed before the Tx section to facilitate clean clocking to the Tx.
For ADV78XX and ICs with external memory, the memory controller should be reset AFTER the memory configuration is complete.