03/07/19 ROM killed video

The 3/7/19 ROM with the video changes has caused my BB -xM to start with a blank screen. In fact the lamp on the monitor is showing that it isn’t receiving anything. Do I need to change a setting or is it a bug?

Maybe a bug in the SyncPol changes in s/vdu/vdudriver. In old code R10 is set to either “0” or R8 depending on interlacing field. In new code it is set to either “0” or “1” depending on interlacing sync and field.

The new code seems to assume that the interlaced field without interlaced sync is invalid and that the value in R8 was always 1.

video changes has caused my BB -xM to start with a blank screen

Oh dear, I’ll give it a test here – one of the perils of me making a change in April is I’ve forgotten what I did!

Maybe a bug in the SyncPol changes in s/vdu/vdudriver. In old code R10 is set to either “0” or R8 depending on interlacing field. In new code it is set to either “0” or “1” depending on interlacing sync and field.

In the old code finding the control list item (R8) set to 1 was equivalent to interlaced sync and field and shouldn’t escape the function in R10 – it’s only used to set the ModeFlags & width shift. Now, we pick that from the SyncPol word rather than the control list, so I think it’s equivalent. E&OE.

Sprow replaces the fuse and the lights come back on (sooner if I’d noticed the change of date).