PIC18F8722-I/PT Microchip Technology Inc., PIC18F8722-I/PT Datasheet - Page 314

• Manufacturer Part Number: PIC18F8722-I/PT
• Description: 80 PIN, 128 KB FLASH, 4K RAM, 70 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC18F8722-I/PT

• A/d Inputs: 16-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 10 MIPS
• Eeprom Memory: 1024 Bytes
• Input Output: 70
• Interface: SPI/I2C/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 80-pin TQFP
• Programmable Memory: 128K Bytes
• Ram Size: 3.9K Bytes
• Speed: 40 MHz
• Timers: 2-8 bit, 3-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC18F8722 FAMILY
25.2
For the PIC18F8722 family of devices, the WDT is
driven by the INTRC source. When the WDT is
enabled, the clock source is also enabled. The nominal
WDT period is 4 ms and has the same stability as the
INTRC oscillator.
The 4 ms period of the WDT is multiplied by a 16-bit
postscaler. Any output of the WDT postscaler is
selected by a multiplexor, controlled by bits in
Configuration Register 2H. Available periods range
from 4 ms to 131.072 seconds (2.18 minutes). The
WDT and postscaler are cleared when any of the
following events occur: a SLEEP or CLRWDT instruction
is executed, the IRCF bits (OSCCON<6:4>) are
changed or a clock failure has occurred.
FIGURE 25-1:
DS39646B-page 312
Change on IRCF bits
All Device Resets
INTRC Source
WDTPS<4:1>
Watchdog Timer (WDT)
SWDTEN
CLRWDT
WDTEN
Sleep
WDT BLOCK DIAGRAM
Enable WDT
WDT Counter
÷128
4
Preliminary
Programmable Postscaler
1:1 to 1:32,768
25.2.1
Register 25-15 shows the WDTCON register. This is a
readable and writable register which contains a control
bit that allows software to override the WDT enable
configuration bit, but only if the configuration bit has
disabled the WDT.
Note 1: The CLRWDT and SLEEP instructions
2: Changing the setting of the IRCF bits
3: When a CLRWDT instruction is executed,
CONTROL REGISTER
clear the WDT and postscaler counts
when executed.
(OSCCON<6:4>) clears the WDT and
postscaler counts.
the postscaler count will be cleared.
Reset
 2004 Microchip Technology Inc.
WDT
Reset
Wake-up from
Power-Managed
Modes