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Portable_Speed2
Programmer's Reference Manuals
» Part 15 – SWI Calls
» Portable
» Portable_Speed2
Portable_Speed2
(SWI &42FCE)
| Entry | |
|---|---|
| R0 | Reason code |
| All other registers are dependent on reason code | |
| Exit | |
|---|---|
| All registers dependent on reason code | |
Use
The purpose of this call is to provide extra functionality not available through Portable_Speed.
Notes
The action performed depends on the reason code value in R0.
Reason Codes
| # | Hex # | Action |
|---|---|---|
| 00 | &00 | Report current CPU speed in MHz |
| 01 | &01 | Report min & max CPU speed in MHz |
| 02 | &02 | Set 'slow' and 'fast' speeds in MHz |
| 03 | &03 | Report current 'slow' and 'fast' speeds in MHz |
| 04 | &04 | Report number of CPU speeds available |
| 05 | &05 | Convert speed index to MHz |
| 06 | &06 | Convert MHz to index |
| 07 | &07 | Report current CPU speed as index |
| 08 | &08 | Set 'slow' and 'fast' speeds using indices |
| 09 | &09 | Report current 'slow' and 'fast' speed indices |