Datasheet
PIC16C6X
DS30234E-page 142 1997-2013 Microchip Technology Inc.
FIGURE 13-22: WAKE-UP FROM SLEEP THROUGH INTERRUPT
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.
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
T
OST(2)
PC+2
13.9 Program Verification/Code Protection
If the code protection bit(s) have not been pro-
grammed, the on-chip program memory can be read
out for verification purposes.
13.10 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.
13.11 In-Circuit Serial Programming
The PIC16CXX 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
other lines for power, ground, and the programming
voltage. This allows customers to manufacture boards
with unprogrammed devices, and then program the
microcontroller just before shipping the product. This
also allows the most recent firmware or a custom firm-
ware to be programmed.
Applicable Devices
61 62 62A R62 63 R63 64 64A R64 65 65A R65 66 67
Note: Microchip does not recommend code pro-
tecting windowed devices.
Applicable Devices
61 62 62A R62 63 R63 64 64A R64 65 65A R65 66 67
Applicable Devices
61 62 62A R62 63 R63 64 64A R64 65 65A R65 66 67
The device is placed into a program/verify mode by
holding pins RB6 and RB7 low while raising the MCLR
(VPP) pin from VIL to VIHH (see programming specifica-
tion). RB6 becomes the programming clock and RB7
becomes the programming data. Both RB6 and RB7
are Schmitt Trigger inputs in this mode.
After reset, to place the device in program/verify mode,
the program counter (PC) is at location 00h. A 6-bit
command is then supplied to the device. Depending on
the command, 14-bits of program data are then sup-
plied to or from the device, depending if the command
was a load or a read. For complete details of serial pro-
gramming, please refer to the PIC16C6X/7X Program-
ming Specifications (Literature #DS30228).
FIGURE 13-23: TYPICAL IN-CIRCUIT SERIAL
PROGRAMMING
CONNECTION
External
Connector
Signals
To N or ma l
Connections
To N or ma l
Connections
PIC16CXX
V
DD
VSS
MCLR/VPP
RB6
RB7
+5V
0V
V
PP
CLK
Data I/O
V
DD