PIC16F870-I/SS Microchip Technology, PIC16F870-I/SS Datasheet - Page 98

• Manufacturer Part Number: PIC16F870-I/SS
• Description: IC MCU FLASH 2KX14 EE 28SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F870-I/SS

• Core Size: 8-Bit
• Program Memory Size: 3.5KB (2K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Connectivity: UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Type: FLASH
• Eeprom Size: 64 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SSOP
• Controller Family/series: PIC16F
• No. Of I/o's: 22
• Eeprom Memory Size: 64Byte
• Ram Memory Size: 128Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 8
• 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, ICE2000, DM163022, DV164120
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 28 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: I3-DB16F871 - BOARD DAUGHTER ICEPIC3AC164307 - MODULE SKT FOR PM3 28SSOPAC164020 - MODULE SKT PROMATEII 44TQFPXLT28SS-1 - SOCKET TRANSITION ICE 28SSOP
• Lead Free Status / Rohs Status: Details

PIC16F870/871
FIGURE 11-8:
11.10 Interrupts
The PIC16F870/871 family has up to 14 sources of
interrupt. The Interrupt Control register (INTCON)
records individual interrupt requests in flag bits. It 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. When bit GIE is enabled, and an
interrupt’s flag bit and mask bit are set, the interrupt will
vector immediately. Individual interrupts can be dis-
abled through their corresponding enable bits in vari-
ous registers. Individual interrupt bits are set,
regardless of the status of the GIE bit. The GIE bit is
cleared on RESET.
The “return from interrupt” instruction, RETFIE, exits
the interrupt routine as well as sets the GIE bit, which
re-enables interrupts.
The RB0/INT pin interrupt, the RB port change
interrupt, and the TMR0 overflow interrupt flags are
contained in the INTCON register.
DS30569B-page 96
Note:
INTERNAL RESET
PWRT TIME-OUT
INTERNAL POR
OST TIME-OUT
Individual interrupt flag bits are set,
regardless
corresponding mask bit, or the GIE bit.
MCLR
V
DD
SLOW RISE TIME (MCLR TIED TO V
of
the
status
0V
T
PWRT
of
their
1V
5V
The peripheral interrupt flags are contained in the spe-
cial function registers, PIR1 and PIR2. The correspond-
ing interrupt enable bits are contained in special
function registers, PIE1 and PIE2, and the peripheral
interrupt enable bit is contained in special function
register, INTCON.
When an interrupt is responded to, the GIE bit is
cleared to disable any further interrupt, the return
address is pushed onto the stack and 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 software before re-enabling interrupts to
avoid recursive interrupts.
For external interrupt events, such as the INT pin or
PORTB change interrupt, the interrupt latency will be
three or four instruction cycles. The exact latency
depends when the interrupt event occurs. The latency
is the same for one or two-cycle instructions. Individual
interrupt flag bits are set, regardless of the status of
their corresponding mask bit, PEIE bit, or GIE bit.
DD
)
T
OST
 2003 Microchip Technology Inc.