

#include <nitro/cp.h>void CP_SetSqrtImm64( u64 param );void CP_SetSqrtImm32( u32 param );
| param | Value of the square root to be calculated. |
None.
Sets the parameters for square root calculations. It does not set the square root calculation mode, but merely stores the parameter. Calculation modes are listed below.
| Square Root Calculation Mode | Calculation | Calculation Cycles | CPU Cycle Conversion |
|---|---|---|---|
| CP_SQRT_32BIT_MODE | Square root calculation of 32-bit values | 13 cycles | 26 cycles |
| CP_SQRT_64BIT_MODE | Square root calculation of 64-bit values | 13 cycles | 26 cycles |
Note: With the square root calculator, an interrupt may affect data integrity. If the parameters are set and an interrupt occurs during square root calculation, the result may not be accurate. Therefore, to maintain the integrity of an interrupted square root calculation, temporarily store and restore the calculator status using CP_SaveContext() and CP_RestoreContext(), respectively. The status of square root calculators is also automatically saved/restored when threads are switched.
Example: Restore the status of the square root calculator.
intr_func( void ) { CPContext context; CP_SaveContext( &context ); CP_SetSqrt32( 1000 ); CP_WaitSqrt(); result = CP_GetDqrtResult32(); CP_RestoreContext( &context ); }
Stores values in SQRT_PARAM(0x40002B8) of the IO register.
CP_SetSqrt*
CP_IsSqrtBusy
CP_WaitSqrt
CP_GetSqrtResult*
2006/08/09 Added a note about use inside interrupts.
2004/01/09/ Added content.
2003/12/01 Initial version.
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