GraphicsV 7 (changes)
Showing changes from revision #10 to #11:
Added | Removed | Changed
GraphicsV
» GraphicsV 7
Graphics Vector (42)
| Entry | |
|---|---|
| R0 | Pointer to VIDC List Type 3 |
| R4 | Bits 0-15: 7 (reason code) |
| Bits 16-23: Head number | |
| Bits 24-31: Driver number |
| Exit | |
|---|---|
| R0 | Zero: Mode OK |
| Non-zero: Mode not OK | |
| R4 | 0 |
| - | All other registers preserved |
Use
The kernel issues this call to check whether a driver can support a proposed mode. The appropriate driver should respond by checking the mode parameters, setting R0 appropriately, and setting R4 to 0 to claim the call.
Notes
GraphicsV 19 is an improved version of this call call, which allows the driver to provide additional feedback on the memory requirements of the framebuffer.
For future-proofing, the driver must ensure it checks that the provided VIDC list is a type 3 list.
Instead of calling GraphicsV directly, user software should use OS_CheckModeValid in order to check if a screen mode is valid.
See also
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