PIC16LF1526 Datasheet, PDF (92/354 Pages) Microchip Technology – 64-Pin Flash Microcontrollers with nanoWatt XLP Technology

PIC16(L)F1526/27
8.1.1 WAKE-UP USING INTERRUPTS
When global interrupts are disabled (GIE cleared) and
any interrupt source has both its interrupt enable bit
and interrupt flag bit set, one of the following will occur:
• If the interrupt occurs before the execution of a
SLEEP instruction
- SLEEP instruction will execute as a NOP.
- WDT and WDT prescaler will not be cleared
- TO bit of the STATUS register will not be set
- PD bit of the STATUS register will not be
cleared.
• If the interrupt occurs during or after the execu-
tion of a SLEEP instruction
- SLEEP instruction will be completely exe-
cuted
- Device will immediately wake-up from Sleep
- WDT and WDT prescaler will be cleared
- TO bit of the STATUS register will be set
- PD bit of the STATUS register will be cleared.
Even if the flag bits were checked before executing a
SLEEP instruction, it may be possible for flag bits to
become set before the SLEEP instruction completes. To
determine whether a SLEEP instruction executed, test
the PD bit. If the PD bit is set, the SLEEP instruction
was executed as a NOP.
FIGURE 8-1:
WAKE-UP FROM SLEEP THROUGH INTERRUPT
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
OSC1⁽¹⁾
CLKOUT⁽²⁾
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
TOST⁽³⁾
Interrupt flag
GIE bit
(INTCON reg.)
Instruction Flow
PC
PC
Instruction
Fetched
Inst(PC) = Sleep
Instruction
Executed
Inst(PC - 1)
Processor in
Sleep
PC + 1
Inst(PC + 1)
Sleep
PC + 2
Interrupt Latency⁽⁴⁾
PC + 2
Inst(PC + 2)
Inst(PC + 1)
PC + 2
Dummy Cycle
0004h
Inst(0004h)
Dummy Cycle
0005h
Inst(0005h)
Inst(0004h)
Note 1:
2:
3:
XT, HS or LP Oscillator mode assumed.
CLKOUT is not available in XT, HS or LP Oscillator modes, but shown here for timing reference.
TOST = 1024 TOSC (drawing not to scale). This delay applies only to XT, HS or LP Oscillator modes.
DS41458A-page 92
Preliminary
 2011 Microchip Technology Inc.