[RKKS08]

The statement of several posters auto thyristor flashes do not communicate with the camera is not correct.
This is true only for cheap and/or not brand-dedicated and/or pre-autofocus flashes.

As an example, many flashes of the older Metz MZ series (with the correct SCA modul 3701 or 3702) will in their Auto Mode get and use the camera settings. These are aperture, ISO, and angle of view of the lens (if the camera knows it). So, if the situation does not afford special flash settings, you don't need to adjust anything.
In my experience, this quite often works better than TTL and pTTL.

[mcgregni]

I certainly get the impression that the Pentax AF-540FGZ does not communicate settings information with the camera when in 'A' flash mode ..... for one thing auto Flash Head zoom is not available, and camera aperture /ISO adjustments have no effect on the flash display. The flash needs these settings input directly on its controls to allow correct exposure. Indeed the camera settings can be 'off-set' from those on the flash specifically in order to take exposure control .....

Would your point be related to film - era cameras, not the DSLRs ?