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Using a 30" monitor at 2560 x 1600 with VirtualRPC was not fun as the Display Configuration utility limits the selectable display to only 2048 x 1534.
The alternative was to write specific MDF scripts for new modes.
I have added three (3) new display modes to the default VirtualAcorn (VRPC-SE) monitor file to make use of the large 30" screen at display resolutions of 2560 x 1600.
The definitions are as follows:


The first mode is a Full Screen mode 2560 x 1600 for display outside the Windows desktop.

The 2nd mode is a display setting for use when in the Windows desktop as it adjusts the vertical display for the height of the Windows Taskbar.

The 3rd mode is a display setting for use when in the Windows desktop and adjusts for both the Windows Taskbar and Gadget Bar in Windows Vista.

The VRPC-SE monitor definition file is located in the following directory:
HostFS::HardDisc4.$.!Boot.Resources.Configure.Monitors.VirtualAcorn

it is a text file and you can add the above 3 definitions to the end of the file just before the last line reading #End.

With the above resolutions, as a default, the system will limit you to 32K colours.

Hope someone may find the above helpful.

Cheers.

Mohsen

For info/interest, it does seem to be possible to retain 16M colours in the first two modes by starting up VirtualRPC-SA or -AdjustSA using the ARM7500 emulation (which I believe gives a max screen memory of 16000K).

The memory used for the first 2 modes is 13784K and 14700K respectively.

If the third mode is selected, the colour depth does drop to 32K though, using 'only' 8000K screen memory.

(Presumably the memory would exceed 160000K in 16M colours?)

I haven't tested it, but there doesn't seem to be any noticeable performance hit in these mega-res modes (Intel E6600 processor - 2.40GHz.)

Geoff Peck
pp T.O.M.S.

True.

I discovered that I could get more VRAM (and therefore more colours) when selecting ARM7500 but not when selecting the StrongARM.

2560 x 1600 with 16M colours is possible with ARM7500 but not StrongARM !!!

Why is this?

Mohsen

With VirtualRPC-SA or -AdjustSA, you have a choice of three start-up emulations:

- Both the 'ARM710' and 'StrongARM' options have a limit of 8MB VRAM (the original release was 2MB, just like the real RiscPC). So if you select a combination of display resolution and colour depth which would exceed the current 8MB screen memory limit, normally the colour depth is dropped automatically - usually to 32K - to bring it back within limits.

- The 'ARM7500' option emulates the real A7000 where the 'VRAM' was taken from the machine's main RAM, up to a max of 16MB. So with this option selected, you can achieve a screen res of (say) 1920x1200 or 2048x1536 pixels, both in 16M colours.

The same goes for the first two 2560x1600 modes you provided. The screen memory required in 16M colours is less than 16000k, so that's OK.

But I suspect that with the slightly different settings required for the third mode, the screen memory required will exceed 16000k, so the colour depth is automatically dropped to 32K.

"StrongARM-compatible" software should still run OK with the ARM7500 emulation. If you have any software which specifically *requires* StrongARM to run (IMHO very unlikely), you'll need to select the StrongARM start-up option and limit either screen res and/or colour depth, so as not to exceed the screen memory limit of 8000k.

HTH, Doug Stephenson
pp T.O.M.S.

6+ years after the above thread was published, it can be slightly updated with yet more good news for Fans of Bigger RISC OS Displays.

We've recently taken on a couple of 27" (diagonal) monitors, running in a native resolution of 2560 x 1440 pixels. Note that, if using a DVI-D connection, the monitor cable needs to be the fully-wired DUAL LINK variant. Dual link cables are readily available online for a few quid, e.g. http://www.amazon.co.uk/s/ref=nb_sb_nos ... tor+cables

As for an MDF for RISC OS, simply tweaking the 2560 x 1600 pixel numbers given by mohsen to suit the 2560 x 1440 pixel monitors worked first time. The full-screen RISC OS display, in 16M colours (51Hz), is simply gorgeous. The screen memory required is 14,440K, so 16M colours requires the ARM7500 core emulation. As expected, the StrongARM core drops the colour depth to 32K.

Performance-wise, we do occasionally detect just a very slight 'hesitation' in RISC OS screen redraw, with either a 2-core or 4-core 2.4GHz E6600 processor under the bonnet. But if plugged into an i7 core laptop, also running at 2.4GHz, there is no discernible redraw hesitation on the plug-in monitor display via HDMI. (Both machines running Windows; iMacs not tested.)

The modified MDF is listed in the much-upgraded Technical Support Assistant v2.0 article on http://www.virtualacorn.co.uk/support/a ... /index.htm but do please note that, although we somehow got the kudos, it was mohsen who did all the hard graft on the MDF! No doubt Aaron will fix that when he gets a round tuit.

Jeff Peck
pp T.O.M.S.