We're using the internal colour bars generator in the SD block of the ADV7842. However, I can't seem to work out how to tell it which format to generate (PAL or NTSC). It appears to generate based on the last thing the SD block saw.
At startup, even if I set the V FREQ register to 50 Hz, it seems to generate an NTSC signal. However, if I then switch to a composite input at PAL, and then back to colour bars, the colour bar generator then seems to generate PAL. PRIM_MODE is set to SDP, VID_STD is set to 1 (CVBS).
Can you tell me how I can control which format the colour bar generator generates?