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for ARM devices
Mode Flags (Rev #2, changes)
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Programmer's Reference Manuals
» Part 7 - The Desktop
» The Window Manager
» SWI Calls?
» Wimp_SetMode
» Mode Specifier Block
» Mode Variable Numbers
» Mode Flags
Mode Flags
| Bit | Meaning when set |
|---|---|
| 0 | Non-graphics mode |
| 1 | Teletext mode |
| 2 | Gap mode |
| 3 | BBC gap mode |
| 4 | Hi-res mono mode |
| 5 | Double height VDU chars |
| 6 | Hardware scroll |
| 7 | |
| 65536 colour RGB 5:6:5 mode (only valid if Log2BPP == 4) | |
| 8 | Interlaced mode, with hardware using two separate framebuffers. |
| 9 | Greyscale palette, gradient from black to white (only valid in palletised modes) |
| Indicates chroma sub-sampling mode (if Log2BPP == 7) | |
| 10-11 | Reserved |
| 12-15 | Data format and colour space information |
Bits 12 and 13 specify the basic data format/colour space. Bits 14 and 15 then give further details, to describe a number of sub-formats.
| Data format | Sub format | Meaning |
|---|---|---|
| (bits 12-13) | (bits 14-15) | |
| 00: RGB | bit 14 | RGB order (0=VIDC style &BGR, 1=&RGB) |
| bit 15 | Alpha mode (0=transparency/supremacy, 1=alpha) | |
| 01: Misc | 00 | CMYK |
| Other | Reserved | |
| 10: YCbCr | bit 14 | range (0=full, 1=video) |
| bit 15 | standard (0=ITU-R BT.601, 1=ITU-R BT.709) | |
| 11: Reserved |
Notes
The bits in the returning register when using OS_ReadModeVariables provides the information (as shown above) about the current screen mode.
See also
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