Power Management
15-29
Clock Generation and System Reset Management
Figure 15–12. Code Example (Continued)
the_end:
adr r2, into_ 1
bx
r2
.state16
into_16_bis:
nop
nop
nop
nop
nop
nop
nop
nop
nop
nop
pop
{r1–r7}
pop
{pc}
;
CONSTANT TABLE
;
ARM_IDLECT1 .long 0xFFFECE04
Example:
-
If the reference clock speed = 12 MHz, then MPU clock speed = 96 MHz
-
If the above routine is used after the write to ARM_IDLECT1 register, you
need 4 * 96/12 + 2 + 3 = 37 clock cycles
To achieve this, run the loop seven times.