PIC16F/LF1946/47
FIGURE 7-4:
INT PIN INTERRUPT TIMING
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
(3)
CLKOUT
(4)
INT pin
INTF
(1)
(1)
(2)
(5)
Interrupt Latency
GIE
INSTRUCTION FLOW
PC
PC + 1
—
0004h
0005h
PC
Inst (PC)
PC + 1
Instruction
Fetched
Inst (PC + 1)
Inst (0004h)
Inst (0005h)
Inst (0004h)
Instruction
Executed
Dummy Cycle
Dummy Cycle
Inst (PC)
Inst (PC – 1)
Note 1: INTF flag is sampled here (every Q1).
2: Asynchronous interrupt latency = 3-5 TCY. Synchronous latency = 3-4 TCY, where TCY = instruction cycle time.
Latency is the same whether Inst (PC) is a single cycle or a 2-cycle instruction.
3: CLKOUT not available in all Oscillator modes.
4: For minimum width of INT pulse, refer to AC specifications in Section 29.0 “Electrical Specifications”.
5: INTF is enabled to be set any time during the Q4-Q1 cycles.
2010 Microchip Technology Inc.
Preliminary
DS41414A-page 87
MICROCHIP [ MICROCHIP ]
