PIC16F639-I/SS Microchip Technology, PIC16F639-I/SS Datasheet - Page 65

• Manufacturer Part Number: PIC16F639-I/SS
• Description: IC MCU FLASH 2KX14 20SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F639-I/SS

• Program Memory Type: FLASH
• Program Memory Size: 3.5KB (2K x 14)
• Package / Case: 20-SSOP
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: Brown-out Detect/Reset, LVD, POR, WDT
• Number Of I /o: 11
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: SPI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT20SS1-1 - SOCKET TRANSITION 20DIP 20SSOPXLT20SS-1 - SOCKET TRANSITION 18DIP 20SSOPAC162066 - HEADER INTRFC MPLAB ICD2 20PINAC164307 - MODULE SKT FOR PM3 28SSOP
• Eeprom Size: -
• Data Converters: -
• Connectivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

9.4
The PIC16F630/676 has 7 sources of interrupt:
• External Interrupt RA2/INT
• TMR0 Overflow Interrupt
• PORTA Change Interrupts
• Comparator Interrupt
• A/D Interrupt (PIC16F676 only)
• TMR1 Overflow Interrupt
• EEPROM Data Write Interrupt
The Interrupt Control register (INTCON) and Peripheral
Interrupt register (PIR) record individual interrupt
requests in flag bits. The INTCON register also has
individual and global interrupt enable bits.
A global interrupt enable bit, GIE (INTCON<7>) enables
(if set) all unmasked interrupts, or disables (if cleared) all
interrupts. Individual interrupts can be disabled through
their corresponding enable bits in INTCON register and
PIE register. GIE is cleared on RESET.
The return from interrupt instruction,
interrupt routine, as well as sets the GIE bit, which re-
enables unmasked interrupts.
The following interrupt flags are contained in the
INTCON register:
• INT pin interrupt
• PORTA change interrupt
• TMR0 overflow interrupt
The peripheral interrupt flags are contained in the
special register PIR1. The corresponding interrupt
enable bit is contained in Special Register PIE1.
The following interrupt flags are contained in the PIR
register:
• EEPROM data write interrupt
• A/D interrupt
• Comparator interrupt
• Timer1 overflow interrupt
When an interrupt is serviced:
• The GIE is cleared to disable any further interrupt
• The return address is pushed onto the stack
• The PC is loaded with 0004h
Once in the Interrupt Service Routine, the source(s) of
the interrupt can be determined by polling the interrupt
flag bits. The interrupt flag bit(s) must be cleared in soft-
ware before re-enabling interrupts to avoid RA2/INT
recursive interrupts.
For external interrupt events, such as the INT pin, or
PORTA change interrupt, the interrupt latency will be
three or four instruction cycles. The exact latency
depends upon when the interrupt event occurs (see
Figure 9-11). The latency is the same for one or two-
cycle instructions. Once in the Interrupt Service
Routine, the source(s) of the interrupt can be
determined by polling the interrupt flag bits. The
 2003 Microchip Technology Inc.
Interrupts
RETFIE
, exits
interrupt flag bit(s) must be cleared in software before
re-enabling interrupts to avoid multiple interrupt
requests.
Note 1: Individual interrupt flag bits are set,
2: When an instruction that clears the GIE
regardless
corresponding mask bit or the GIE bit.
bit is executed, any interrupts that were
pending for execution in the next cycle
are ignored. The interrupts which were
ignored are still pending to be serviced
when the GIE bit is set again.
PIC16F630/676
of
the
status
DS40039C-page 63
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