KS57C2308/P2308/C2316/P2316
SAM47 INSTRUCTION SET
5-53
IDLE
—
Idle Operation
IDLE
Operation:
Operand
Operation Summary
Bytes
Cycles
–
Engage CPU idle mode
2
2
Description:
IDLE causes the CPU clock to stop while the system clock continues oscillating by setting bit 2 of
the power control register (PCON). After an IDLE instruction has been executed, peripheral
hardware remains operative.
In application programs, an IDLE instruction must be immediately followed by at least three NOP
instructions. This ensures an adequate time interval for the clock to stabilize before the next
instruction is executed. If more than three NOP instructions are not used after IDLE instruction,
leakage current could be flown because of the floating state in the internal bus.
Operand
Binary Code
Operation Notation
–
1
1
1
1
1
1
1
1
PCON.2
←
1
1
0
1
0
0
0
1
1
Example:
The instruction sequence
IDLE
NOP
NOP
NOP
sets bit 2 of the PCON register to logic one, stopping the CPU clock. The three NOP instructions
provide the necessary timing delay for clock stabilization before the next instruction in the
program sequence is executed.
Summary of Contents for KS57C2308
Page 30: ...ADDRESS SPACES KS57C2308 P2308 C2316 P2316 2 22 NOTES ...
Page 168: ...SAM47 INSTRUCTION SET KS57C2308 P2308 C2316 P2316 5 94 NOTES ...
Page 170: ......
Page 206: ...POWER DOWN KS57C2308 P2308 C2316 P2316 8 8 NOTES ...
Page 210: ...RESET KS57C2308 P2308 C2316 P2316 9 4 NOTES ...
Page 222: ...I O PORTS KS57C2308 P2308 C2316 P2316 10 12 NOTES ...
Page 272: ...LCD CONTROLLER DRIVER KS57C2308 P2308 C2316 P2316 12 24 NOTES ...
Page 280: ...SERIAL I O INTERFACE KS57C2308 P2308 C2316 P2316 13 8 NOTES ...
Page 294: ...MECHANICAL DATA KS57C2308 P2308 C2316 P2316 15 2 NOTES ...
Page 310: ...KS57P2308 P2316 OTP KS57C2308 P2308 C2316 P2316 16 16 NOTES ...
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