OS_CallBack (changes)
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OS SWI Calls
» OS_CallBack
OS_CallBack
(SWI &15)
| Entry | |
|---|---|
| R0 | Address of the register save block, 0 to read |
| R1 | Address of the callback handler, 0 to read |
| Exit | |
|---|---|
| R0 | Address of previous register save block |
| R1 | Address of previous callback handler |
Use
OS_CallBack sets up the address of the CallBack handler and the its register save block.
Notes
The register save block must be word-aligned and 16 words long.
This call is deprecated and should not be used. Please use OS_ChangeEnvironment instead. Internally, this SWI just calls OS_ChangeEnvironment
This sets up the address of the CallBack handler and the register save block, zero for either value meaning no change – hence you can read the current value.
For Once information a on CallBack handler has been installed, you can request callbacks refer via to OS_AddCallBack OS_SetCallBack.
For information on callbacks refer to CallBack Handler.
See also
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