PIC16C433-I/P Microchip Technology, PIC16C433-I/P Datasheet - Page 65

• Manufacturer Part Number: PIC16C433-I/P
• Description: IC MCU CMOS 8BIT 10MHZ 2K 18-DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16C433-I/P

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 10MHz
• Connectivity: LIN (Local Interconnect Network)
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Size: 3.5KB (2K x 14)
• Program Memory Type: OTP
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 4x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 18-DIP (0.300", 7.62mm)
• For Use With: DVA16XP185 - ADAPTER DEVICE ICE 18DIP/SOICAC164030 - MODULE SKT PROMATEII 28DIP/SOICDVA16XP140 - ADAPTER DEVICE FOR MPLAB-ICE
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

EXAMPLE 9-2:
9.7
The Watchdog Timer is a free running, on-chip RC oscil-
lator which does not require any external components.
This RC oscillator is separate from the RC oscillator of
the OSC1/CLKIN pin. That means that the WDT will run,
even if the clock on the OSC1/CLKIN and OSC2/CLK-
OUT pins of the device has been stopped, for example,
by execution of a SLEEP instruction. During normal oper-
ation, a WDT timeout generates a device RESET
(Watchdog Timer Reset). If the device is in SLEEP
mode, a WDT timeout causes the device to wake-up and
continue with normal operation (Watchdog Timer Wake-
up). The WDT can be permanently disabled by clearing
configuration bit WDTE (Section 9.1).
9.7.1
The WDT has a nominal timeout period of 18 ms (with
no prescaler). The timeout periods vary with tempera-
ture, V
DC specs). If longer timeout periods are desired, a
prescaler with a division ratio of up to 1:128 can be
assigned to the WDT under software control, by writing
to the OPTION register. Thus, timeout periods up to 2.3
seconds can be realized.
The CLRWDT and SLEEP instructions clear the WDT
and the postscaler, if assigned to the WDT, and prevent
it from timing out early and generating a premature
device RESET condition.
The TO bit in the STATUS register will be cleared upon
a Watchdog Timer timeout.
9.7.2
It should also be taken into account that under worst
case conditions (V
Max. WDT prescaler), it may take several seconds
before a WDT timeout occurs.
See Example 7-1 and Example 7-2 for changing pres-
caler between WDT and Timer0.
 2002 Microchip Technology Inc.
MOVWF
MOVF
MOVWF
:
:(ISR)
:
MOVF
MOVWF
SWAPF
SWAPF
RETFIE
Note:
DD
Watchdog Timer (WDT)
WDT PERIOD
WDT PROGRAMMING CONSIDERATIONS
and process variations from part to part (see
When the prescaler is assigned to the
WDT, always execute a CLRWDT instruc-
tion before changing the prescale value,
otherwise a WDT Reset may occur.
W_TEMP
STATUS,W
STATUS_TEMP
STATUS_TEMP,W
STATUS
W_TEMP,F
W_TEMP,W
DD
= Min., Temperature = Max., and
Saving STATUS and W Registers using Shared RAM (0x70 - 0x7F)
;Copy W to TEMP register (bank independent)
;Move STATUS register into W
;Save contents of STATUS register
;Retrieve copy of STATUS register
;Restore pre-isr STATUS register contents
;
;Restore pre-isr W register contents
;Return from interrupt
Preliminary
PIC16C433
DS41139B-page 63