PIC16F870-I/SS Microchip Technology, PIC16F870-I/SS Datasheet - Page 138

• 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

PICmicro MID-RANGE MCU FAMILY
8.7
DS31008A-page 8-16
Design Tips
Question 1:
Answer 1:
Assuming that the algorithm is correct and that interrupts are enabled during the algorithm,
ensure that are registers that are used by the algorithm and by the interrupt service routine are
saved and restored. If not some registers may be corrupted by the execution of the ISR.
Question 2:
Answer 2:
If interrupts are being used, ensure that the interrupt flag is cleared after servicing that interrupt
(but before executing the RETFIE instruction). If the interrupt flag remains set when the RETFIE
instruction is executed, program execution immediately returns to the interrupt vector, since there
is an outstanding enabled interrupt.
An algorithm does not give the correct results.
My system seems to lock up.
1997 Microchip Technology Inc.