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OS_Heap
Programmer's Reference Manuals
» Part 15 – SWI Calls
» OS
» OS_Heap
OS_Heap
(SWI &1D)
| Entry | |
|---|---|
| R0 | Reason code |
| R1 | Pointer to heap |
| All other registers are dependent on reason code | |
| Exit | |
|---|---|
| R0 | Preserved |
| R1 | Preserved |
| All other registers dependent on reason code | |
Use
The purpose of this call is to perform various operations on the heap.
Notes
The action performed depends on the reason code value in R0. It is not yet possible to compact the heap using this call.
Reason Codes
| # | Hex # | Action |
|---|---|---|
| 0 | &00 | Initialise heap |
| 1 | &01 | Describe heap |
| 2 | &02 | Claim block |
| 3 | &03 | Release block |
| 4 | &04 | Change size of block |
| 5 | &05 | Change size of heap |
| 6 | &06 | Read block size |
| 7 | &07 | Get area aligned |