Datasheet

PIC16C62B/72A
DS35008C-page 66 Preliminary 1998-2013 Microchip Technology Inc.
FIGURE 10-10: WAKE-UP FROM SLEEP THROUGH INTERRUPT
10.14 Program Verification/Code Protection
If the code protection bits have not been programmed,
the on-chip program memory can be read out for verifi-
cation purposes.
10.15 ID Locations
Four memory locations (2000h - 2003h) are designated
as ID locations where the user can store checksum or
other code-identification numbers. These locations are
not accessible during normal execution, but are read-
able and writable during program/verify. It is recom-
mended that only the 4 least significant bits of the ID
location are used.
For ROM devices, these values are submitted along
with the ROM code.
10.16 In-Circuit Serial Programming
PIC16CXXX microcontrollers can be serially pro-
grammed while in the end application circuit. This is
simply done with two lines for clock and data, and three
more lines for power, ground and the programming volt-
age. This allows customers to manufacture boards with
unprogrammed devices, and then program the micro-
controller just before shipping the product. This also
allows the most recent firmware or a custom firmware
to be programmed.
For complete details of serial programming, please
refer to the In-Circuit Serial Programming (ICSP™)
Guide, DS30277.
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1
CLKOUT(4)
INT pin
INTF flag
(INTCON<1>)
GIE bit
(INTCON<7>)
INSTRUCTION FLOW
PC
Instruction
fetched
Instruction
executed
PC PC+1 PC+2
Inst(PC) = SLEEP
Inst(PC - 1)
Inst(PC + 1)
SLEEP
Processor in
SLEEP
Interrupt Latency
(Note 2)
Inst(PC + 2)
Inst(PC + 1)
Inst(0004h)
Inst(0005h)
Inst(0004h)
Dummy cycle
PC + 2 0004h 0005h
Dummy cycle
TOST(2)
PC+2
Note 1: XT, HS or LP oscillator mode assumed.
2: T
OST = 1024TOSC (drawing not to scale) This delay will not be there for RC osc mode.
3: GIE = '1' assumed. In this case after wake- up, the processor jumps to the interrupt routine. If GIE = '0', execution will continue in-line.
4: CLKOUT is not available in these osc modes, but shown here for timing reference.
Note: Microchip does not recommend code pro-
tecting windowed devices.