OS_ScreenMode 68
OS SWI Calls
» OS_ScreenMode
» OS_ScreenMode 68
OS_ScreenMode 68
(SWI &65)
| Entry | |
|---|---|
| R0 | 68 |
| R1 | GraphicsV Device driver number to return details of, or -2 to return the ID of the first valid driver |
| R2 | Flags (reserved, should be zero) |
| Exit | |
|---|---|
| R1 | ID of next driver, or -2 if no more to enumerate |
| R2 | Driver flags on registration (R1 of OS_ScreenMode 64) |
| R3 | Driver name on registration (R2 of OS_ScreenMode 64) |
| R4 | Driver state: |
| 0 = Driver is invalid/unallocated (R2-R3 invalid) | |
| 1 = Driver is initialising or shutting down and cannot be used | |
| 2 = Driver is ready for use | |
| All other registers preserved | |
Use
This call is used to enumerate the list of registered GraphicsV Device drivers and to read basic details about them.
Notes
When calling GraphicsV manually, it is only safe to interact with drivers which are in state 2. This state corresponds to a driver which has called both OS_ScreenMode 64 and OS_ScreenMode 65.
To determine the current driver, pass -1 to OS_ScreenMode 11.
See also
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