www.virtualacorn.co.uk/forum

What screen modes are available in VRPC? Is it limited to the modes available in a real RPC, or can it exceed these?

John

It is limited to whatever you can fit in 2Mb of VRAM which is a bit more than a VIDC20 can achieve due to its bandwidth restrictions.

So:
800x600x16m
1152x864x32k
1600x1200x256
2048x1536x16

Etc. You may have to update the bandwidth limit file and or create new mode definitions.

Graeme

OK, thanks. How do you work out what's possible? For example, you quote 1152x864x32k - is 1280x1024x32k possible?

I assume that I would use MakeModes to create new MDFs? Which monitor does VRPC emulate? Is there a monitor definition provided that can be simply used to create new modes?

TiA

John

1280x1024x2 = 2.5Mb so no it isn't supported yet.

VRPC doesn't pretend to be any particular monitor, it'll cope with anything you throw at it although the higher the refresh rate, the slower the emulation is likely to be. I find around 75hz is about right.

Graeme

Do you have to match the monitor inside VRPC to the refresh rate of the real monitor you're using? I assume that, if running in windowed mode (which I do), there's no need to ensure that you're using the right monitor definition?

John

The frame rate displayed on the monitor is unrelated to the frame
rate set inside RISC OS. From inside RISC OS you can choose
from 1 of three frame rates for each mode, 75, 51 and 30 Hz. Changing
the value alters the number of frames per second RISC OS draws. The
actual frame rate displayed on the monitor is set from the VirtualAcorn
display properties window that contains both a Min and a Max value.

VirtualAcorn will try and choose the highest refresh rate it can that
falls between these two values.

For example I run VirtualRPC-SE at 51Hz, but the monitor
displays the screen image at 85Hz (because that's the value
I have set as Max).

At the moment I'm viewing this with a Neovo F-419 19" flat screen monitor and would like to know if it is possible to use the 1280 x 1024 screen mode with more colours?

Currently, I'm using the VirtualRPC-SE monitor definition file with RISC OS Select 4.37 and this only allows me to have 256 colours selected.

As I've never really been able to get my head around Monitor definition files, any help would be much appreciated.

Cheers,Andrew

You can only display modes that use more than 2Mb of VRAM using RISC OS 4 (assuming your copy of VRPC-SE came with that feature - if not visit the downloads section of our website). If you softload Select then the feature is "lost" as it's part of the OS.

VirtualRPC-Adjust, with RISC OS 4.39, can display modes that use greater than 2MB of VRAM, we hope to be able to offer an upgrade soon.