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for ARM devices
OS_ReadPalette
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_ReadPalette
OS_ReadPalette
(SWI &2F)
| Entry | |
|---|---|
| R0 | Logical colour |
| R1 | Type of colour: |
| 16 = normal colour | |
| 24 = Border colour | |
| 25 = Pointer colour |
| Exit | |
|---|---|
| R0 |
Use
The purpose of this call is to read the setting of a particular colour that is sent to the hardware.
Notes
If R2 = R3 on exit the colour requested is a non flashing colour. The values are to interpret as follows:
| Bits | Meaning |
|---|---|
| 0-6 | Value showing how colour was programmed |
| 7 | Supremacy bit |
| 8-15 | Amount of red |
| 16-23 | Amount of green |
| 24-31 | Amount of blue |
The bottom byte returns the second parameter to the VDU 19 command. For example:
| Value | Meaning |
|---|---|
| 0-15 | Actual colour (BBC compatible) |
| 16 | Defined by giving amounts of R, G and B |
| 17-18 | Flashing colour defined by giving amounts of red, green and blue |