On a custom project, I use the ADV7391 in square pixel mode to generate PAL 625i.
I verified the vertical blanking and I noticed an non-compliance to the UIT-R BT.1700 (or ITU-R BT.470-6).
Indeed, on this standard, the "m" present 5 pulses.
Is there a register that control this characteristic ?
Did you refer these threads? believe that it would be helpful to refer
Line-Blanking interval of AD7390's output
[ADV7391] PAL Output