RISC OS 3.7 User Guide
Appendix F: Old-type screen modes
This appendix gives information about the numbered screen modes that were used with earlier versions of the RISC OS operating system. This information is only needed for backward compatibility purposes: for example, you may be using an old software application or game that demands a particular old type screen mode.
Display manager
This section gives a quick recap on how the new screen Display manager operates and where to find more information.
In the Screen configuration option of !Boot, the type of monitor used with your computer is defined. This controls the selection of resolutions used by the Display manager. The Screen configuration option of !Boot is described in Screen on page 40.
Use the Display manager to choose the display resolution and number of colours used by the desktop. The Display manager is described in Desktop colour and resolution on page 13.
The display options that your monitor can use depend upon the characteristics of your monitor. These characteristics are described in a special file called a ModeInfo file. This file is tuned to each monitor type and should not normally be changed. If there is no monitor type for your particular monitor you should contact your Acorn dealer for information.
Backward compatible screen modes
This computer still supports old type screen modes. Screen modes were the way colours and resolutions were selected in the RISC OS 3.1, RISC OS 3.0 and RISC OS 2 operating systems.
There are several reasons why you may want to use an old type screen mode:
- To play a game that demands an old type screen mode.
- To use an application that demands an old type screen mode.
- To generate old type sprite files using !Paint.
Choosing a backward compatible mode
You can choose old-type numbered modes from the Display manager icon bar menu. Choose the Mode window, delete any information in the box, and then type in the mode number you want to use. Click on OK.
If your chosen mode is not available, the Display manager will substitute one with the same number of colours.
Old type sprite files
Your computer uses a new sprite file format, the file type used to save !Paint pictures. However you cannot use one of these new format sprite files on a computer running RISC OS 3.1 or earlier. If you want to use a sprite on a computer running an earlier version of the operating system you should create it while using one of the backward compatible screen modes. Alternatively the graphic translator application !ChangeFSI can convert between sprite types.
Mode table
The table of modes on the following pages show:
- The mode number.
- The text resolution in columns rows.
- The graphics resolution in pixels, which corresponds to the clarity of the mode's display.
- The number of colours available.
- The monitor types that support that mode:
0 : Standard monochrome or colour monitor 1 : Multi frequency monitor
3 : VGA-type monitor
4 : Super VGA-type monitor
List of screen modes
This is the list of screen modes supplied with RISC OS. Third party suppliers may produce software and hardware that produces different video modes; such modes are not listed here.
Mode: Text resolution: Pixel resolution: Logical colours: Monitor types: Desktop mode: Notes
- 0: 80 x 32: 640 x 256: 2: 0,1,3,4: Yes: 3
- 1: 40 x 32: 320 x 256: 4: 0,1,3,4: Yes: 3
- 2: 20 x 32: 160 x 256: 16: 0,1,3,4: 3
- 3: 80 x 25: Text only: 2: 0,1,3,4: 3,4,6
- 4: 40 x 32: 320 x 256: 2: 0,1,3,4: 3
- 5: 20 x 32: 160 x 256: 4: 0,1,3,4: 3
- 6: 40 x 25: Text only: 2: 0,1,3,4: 3,4,6
- 7: 40 x 25: Teletext: 16: 0,1,3,4: 3,4
- 8: 80 x 32: 640 x 256: 4: 0,1,3,4: Yes: 3
- 9: 40 x 32: 320 x 256: 16: 0,1,3,4: Yes: 3
- 10: 20 x 32: 160 x 256: 256: 0,1,3,4: 3
- 11: 80 x 25: 640 x 250: 4: 0,1,3,4: Yes: 3
- 12: 80 x 32: 640 x 256: 16: 0,1,3,4: Yes: 3
- 13: 40 x 32: 320 x 256: 256: 0,1,3,4: Yes: 3
- 14: 80 x 25: 640 x 250: 16: 0,1,3,4: Yes: 3
- 15: 80 x 32: 640 x 256: 256: 0,1,3,4: Yes: 3
- 16: 132 x 32: 1056 x 256: 16: 0,1: Yes: 5
- 17: 132 x 25: 1056 x 250: 16: 0,1: Yes: 5
- 18: 80 x 64: 640 x 512: 2: 1: Yes
- 19: 80 x 64: 640 x 512: 4: 1: Yes
- 20: 80 x 64: 640 x 512: 16: 1: Yes
- 21: 80 x 64: 640 x 512: 256: 1: Yes
- 22: 96 x 36: 768 x 288: 16: 0,1: Yes: 1
- 23: High resolution monochrome monitor only
- 24: 132 x 32: 1056 x 256: 256: 0,1: Yes: 5
- 25: 80 x 60: 640 x 480: 2: 1,3,4: Yes
- 26: 80 x 60: 640 x 480: 4: 1,3,4: Yes
- 27: 80 x 60: 640 x 480: 16: 1,3,4: Yes
- 28: 80 x 60: 640 x 480: 256: 1,3,4: Yes
- 29: 100 x 75: 800 x 600: 2: 1,4: Yes: 1,2
- 30: 100 x 75: 800 x 600: 4: 1,4: Yes: 1,2
- 31: 100 x 75: 800 x 600: 16: 1,4: Yes: 1,2
- 32: 100 x 75: 800 x 600: 256: 1,4: Yes: 1,2,7
- 33: 96 x 36: 768 x 288: 2: 0,1: Yes: 1
- 34: 96 x 36: 768 x 288: 4: 0,1: Yes: 1
- 35: 96 x 36: 768 x 288: 16: 0,1: Yes: 1
- 36: 96 x 36: 768 x 288: 256: 0,1: Yes: 1
- 37: 112 x 44: 896 x 352: 2: 1: Yes: 1
- 38: 112 x 44: 896 x 352: 4: 1: Yes: 1
- 39: 112 x 44: 896 x 352: 16: 1: Yes: 1
- 40: 112 x 44: 896 x 352: 256: 1: Yes: 1
- 41: 80 x 44: 640 x 352: 2: 1,3,4: Yes: 1,3
- 42: 80 x 44: 640 x 352: 4: 1,3,4: Yes: 1,3
- 43: 80 x 44: 640 x 352: 16: 1,3,4: Yes: 1,3
- 44: 80 x 25: 640 x 200: 2: 1,3,4: Yes: 1,3
- 45: 80 x 25: 640 x 200: 4: 1,3,4: Yes: 1,3
- 46: 80 x 25: 640 x 200: 16: 1,3,4: Yes: 1,3
- 47: 45 x 60: 360 x 480: 256: 1,3,4: Yes: 1,7
- 48: 40 x 60: 320 x 480: 16 : 1,3,4: Yes: 1,7
- 49: 40 x 60: 320 x 480: 256: 1,3,4: Yes: 1,7
Notes
- 1 These modes were not available in RISC OS 2.00, nor (except for mode 31) were they available in RISC OS 2.01.
- 2 These modes are not available on early models of RISC OS computers (i.e. the Archimedes 300 series, 440, and 400/1 series, and the BBC A3000).
- 3 If you are using a VGA or Super-VGA-type monitor, these modes are all displayed on a screen having 352 raster lines. Where a mode has fewer than 352 vertical pixels, it is centred on the screen with blank lines at the top and bottom. Because of their appearance these modes are known as letterbox modes. The refresh rate is 70Hz.
- 4 These modes provide compatibility with BBC and Master series computers.
- 5 In these modes circles, arcs, sectors and segments do not look circular. This is because the aspect ratio of the pixels is not in a 1:2, 1:1 or 2:1 ratio.
- 6 These are gap modes, where the colour of the gaps is not necessarily the same as the text background.
- 7 These modes were not available in earlier versions of the operating system.
256 colour modes
In 256 colour modes, there are some restrictions on the control of the colours. Only 64 base colours may be selected; 4 levels of tinting turn the base colours into 256 shades. Also, the selection from the colour palette of 4096 shades is only possible in groups of 16.
Monitor types
If you attempt to select a mode which is not appropriate to the current monitor type, a suitable mode for that monitor is used.
Monitor types and screen modes
Not all monitors can display all of the old type screen modes. The following table lists the screen modes each monitor can display:
Mode: Multi-freq monitor: VGA & LCD monitor: Super VGA monitor
- 0 - 15: Yes: Yes (See Note 1): Yes (See Note 1)
- 16,17: Yes : No : No
- 18 - 21: Yes : No : No
- 22: Yes : No : No
- 23: Not supported: Not supported: Not supported
- 24: Yes : No : No
- 25 - 28 : Yes: Yes: Yes
- 29 - Yes : No: Yes
- 32: Yes: No: Yes
- 33 - 36 : Yes : No : No
- 37 - 40: Yes : No : No
- 41 - 46: Yes: Yes: Yes
- 47: Yes: Yes: Yes
- 48-49: Yes: Yes: Yes
Note 1: VGA and Super VGA type monitors can display modes 0 to 15 with reduced height (letterbox mode). These modes are retained for compatibility.
RISC OS 3.7 User Guide - 20 JAN 1997