AFK60 monitor connected to Raspberry Pi

Has anyone tried connecting an AFK60 monitor to the Raspberry Pi using an HDMI to VGA converter ?.

I bought the "Cable Matters’ converter from Amazon, most of the reviews said to worked fine with the Pi.

Using the latest version of RiscOS the screen is not syncing. I can see where the toolbar is. Pressing F12 shoots it up a bit. So something is getting through.

The monitor works fine with a RiscPC.

I think you will need to edit config.txt to tell the pi what screen mode to use, otherwise it will probably be using 1080p

http://elinux.org/RPi_config.txt

I would guess this would be a good start:

hdmi_group=1
hdmi_mode=1

I’m not sure how old AKF60’s are, but it wouldn’t surprise me if it doesn’t support EDID, which might be confusing the GPU firmware a bit. So in addition to specifying which mode to use in config.txt you might also need something like the hdmi_ignore_edid option (or hdmi_edid_file if you can create a suitable fake EDID file!). I’m not sure if there’s much help for either of those two options, beyond what’s listed on the wiki.

but it wouldn’t surprise me if it doesn’t support EDID

I think that’s a certainty. (Remembering that EDID often confuses Acorn machines.)

Also, I think all HDMI to VGA adapters are active (I don’t believe HDMI provides for analog signals at all), but make sure it is active – a passive adapter won’t work, as the Raspberry Pi definitely doesn’t output VGA on its HDMI port.

HDMI to VGA can be done passive with a resistor ladder: http://en.wikipedia.org/wiki/Resistor_ladder , but that can give low quality results.

Thanks very much for your help, I can now see a desktop displayed, but there are a few problems :

- the display is too small to read properly – black space around the desktop on all sides

- the mouse is using a different area than the desktop – i.e. taller and wider than the displayed desktop and clicking on an icon doesn’t work

Anyway, now you have got me going I will experiment further this evening.

You seem to be having a similar problem to that in this thread.

https://www.riscosopen.org/forum/forums/11/topics/1411

The Pi works differently to other machines in that the firmware sets a screen resolution (either automatically or manually) and then the system scales the RISC OS mode to fit.

You probably want to aim for 800×600, maybe 1024×768 and then set RISC OS to match.

this bit may be useful:

to quickly get a sensible screen. press F12 and type
wimpmode 28
then press return a couple of times
this should get a mode you can use.