PIC16F684
FIGURE 12-11:
TYPICAL IN-CIRCUIT
SERIAL PROGRAMMING
CONNECTION
TABLE 12-9: DEBUGGER RESOURCES
Resource
Description
I/O pins
Stack
ICDCLK, ICDDATA
1 level
To Normal
Connections
Program Memory Address 0h must be NOP
External
Connector
Signals
700h-7FFh
*
PIC16F684
For more information, see “MPLAB® ICD 2 In-Circuit
Debugger User’s Guide” (DS51331), available on
Microchip’s web site (www.microchip.com).
+5V
0V
VDD
VSS
VPP
MCLR/VPP/RA3
FIGURE 12-12:
20-Pin PDIP
20-PIN ICD PINOUT
RA1
RA0
CLK
Data I/O
In-Circuit Debug Device
NC
1
2
20
19
18
17
16
15
14
13
12
11
ICDCLK
ICDDATA
ICDMCLR/VPP
VDD
RA5
RA4
3
Vss
RA0
RA1
RA2
4
*
*
*
5
6
RA3
RC5
To Normal
Connections
7
RC0
RC1
RC2
NC
RC4
8
9
RC3
ICD
* Isolation devices (as required)
10
12.11 In-Circuit Debugger
Since in-circuit debugging requires access to the data
and MCLR pins, MPLAB® ICD 2 development with an
14-pin device is not practical. A special 20-pin
PIC16F684 ICD device is used with MPLAB ICD 2 to
provide separate clock, data and MCLR pins and frees
all normally available pins to the user.
A special debugging adapter allows the ICD device to
be used in place of a PIC16F684 device. The
debugging adapter is the only source of the ICD device.
When the ICD pin on the PIC16F684 ICD device is held
low, the In-Circuit Debugger functionality is enabled.
This function allows simple debugging functions when
used with MPLAB ICD 2. When the microcontroller has
this feature enabled, some of the resources are not
available for general use. Table 12-9 shows which
features are consumed by the background debugger.
2004 Microchip Technology Inc.
Preliminary
DS41202C-page 109
MICROCHIP [ MICROCHIP ]
