PIC12F629-I/MF Microchip Technology, PIC12F629-I/MF Datasheet - Page 66

• Manufacturer Part Number: PIC12F629-I/MF
• Description: IC MCU CMOS 8BIT 1K FLASH 8-DFN
• Manufacturer: Microchip Technology
• Series: PIC® 12Fr

Specifications of PIC12F629-I/MF

• Core Size: 8-Bit
• Program Memory Size: 1.75KB (1K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Peripherals: POR, WDT
• Number Of I /o: 5
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 64 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-DFN
• Controller Family/series: PIC12
• No. Of I/o's: 6
• Eeprom Memory Size: 128Byte
• Ram Memory Size: 64Byte
• Cpu Speed: 20MHz
• No. Of Timers: 2
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164324 - MODULE SKT FOR MPLAB 8DFN/16QFNXLT08DFN2 - SOCKET TRANSITION ICE 14DIP/8DFNXLT08DFN - SOCKET TRANSITION ICE 8DFNAC164032 - ADAPTER PICSTART PLUS 8DFN/DIPAC124001 - MODULE SKT PROMATEII 8DIP/SOIC
• Data Converters: -
• Connectivity: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PIC12F629/675
TABLE 9-8:
9.5
During an interrupt, only the return PC value is saved
on the stack. Typically, users may wish to save key
registers during an interrupt, e.g., W register and
STATUS register. This must be implemented in
software.
Example 9-2 stores and restores the STATUS and W
registers. The user register, W_TEMP, must be defined
in both banks and must be defined at the same offset
from the bank base address (i.e., W_TEMP is defined
at 0x20 in Bank 0 and it must also be defined at 0xA0
in Bank 1). The user register, STATUS_TEMP, must be
defined in Bank 0. The Example 9-2:
• Stores the W register
• Stores the STATUS register in Bank 0
• Executes the ISR code
• Restores the STATUS (and bank select bit
• Restores the W register
EXAMPLE 9-2:
DS41190E-page 64
MOVWF
SWAPF
BCF
MOVWF
SWAPF
MOVWF
SWAPF
SWAPF
0Bh, 8Bh INTCON
0Ch
8Ch
Legend: x = unknown, u = unchanged, - = unimplemented read as '0', q = value depends upon condition.
Address
register)
:
:(ISR)
:
W_TEMP
STATUS,W
STATUS,RP0
STATUS_TEMP
STATUS_TEMP,W;swap STATUS_TEMP register into
STATUS
W_TEMP,F
W_TEMP,W
Context Saving During Interrupts
Shaded cells are not used by the Interrupt module.
PIR1
PIE1
Name
SUMMARY OF INTERRUPT REGISTERS
EEIF
EEIE
;copy W to temp register,
;swap status to be saved into W
;change to bank 0 regardless of
;save status to bank 0 register
;move W into STATUS register
;swap W_TEMP
;swap W_TEMP into W
Bit 7
GIE
W, sets bank to original state
SAVING THE STATUS AND
W REGISTERS IN RAM
could be in either bank
current bank
PEIE
ADIF
ADIE
Bit 6
Bit 5
T0IE
—
—
INTE
Bit 4
—
—
GPIE
CMIF
CMIE
Bit 3
9.6
The Watchdog Timer is a free running, on-chip RC
oscillator, which requires no external components. This
RC oscillator is separate from the external RC oscillator
of the CLKIN pin and INTOSC. That means that the
WDT will run, even if the clock on the OSC1 and OSC2
pins of the device has been stopped (for example, by
execution of a
operation, a WDT time-out generates a device RESET.
If the device is in SLEEP mode, a WDT time-out
causes the device to wake-up and continue with normal
operation. The WDT can be permanently disabled by
programming the configuration bit WDTE as clear
(Section 9.1).
9.6.1
The WDT has a nominal time-out period of 18 ms, (with
no prescaler). The time-out periods vary with tempera-
ture, V
DC specs). If longer time-out 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, time-out periods up to
2.3 seconds can be realized.
The
and the prescaler, if assigned to the WDT, and prevent
it from timing out and generating a device RESET.
The TO bit in the STATUS register will be cleared upon
a Watchdog Timer time-out.
9.6.2
It should also be taken in account that under worst case
conditions (i.e., V
WDT prescaler) it may take several seconds before a
WDT time-out occurs.
Bit 2
T0IF
CLRWDT
—
—
DD
Watchdog Timer (WDT)
and process variations from part to part (see
WDT PERIOD
WDT PROGRAMMING
CONSIDERATIONS
INTF
Bit 1
—
—
and
SLEEP
DD
SLEEP
= Min., Temperature = Max., Max.
TMR1IF 00-- 0--0 00-- 0--0
TMR1IE 00-- 0--0 00-- 0--0
GPIF
Bit 0
© 2007 Microchip Technology Inc.
instruction). During normal
instructions clear the WDT
0000 0000 0000 000u
POR, BOD
Value on
Value on all
RESETS
other