PIC16F877A-I/ML Microchip Technology, PIC16F877A-I/ML Datasheet - Page 87

• Manufacturer Part Number: PIC16F877A-I/ML
• Description: IC MCU FLASH 8KX14 A/D 44QFN
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F877A-I/ML

• Core Size: 8-Bit
• Program Memory Size: 14KB (8K x 14)
• Core Processor: PIC
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-QFN
• Controller Family/series: PIC16F
• No. Of I/o's: 33
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 368Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 368 B
• Interface Type: I2C, SPI, USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 33
• Number Of Timers: 1 x 16 bit
• 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: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT44QFN2 - SOCKET TRAN ICE 44QFN/40DIPAC164322 - MODULE SOCKET MPLAB PM3 28/44QFN444-1001 - DEMO BOARD FOR PICMICRO MCU
• Lead Free Status / Rohs Status: Details

5.5
1997 Microchip Technology Inc.
Arithmetic Logical Unit (ALU)
PICmicro MCUs contain an 8-bit ALU and an 8-bit working register. The ALU is a general pur-
pose arithmetic and logical unit. It performs arithmetic and Boolean functions between the data
in the working register and any register file.
Figure 5-3: Operation of the ALU and W Register
The ALU is 8-bits wide and is capable of addition, subtraction, shift and logical operations. Unless
otherwise mentioned, arithmetic operations are two's complement in nature. In two-operand
instructions, typically one operand is the working register (W register). The other operand is a file
register or an immediate constant. In single operand instructions, the operand is either the W reg-
ister or a file register.
The W register is an 8-bit working register used for ALU operations. It is not an addressable reg-
ister.
Depending on the instruction executed, the ALU may affect the values of the Carry (C), Digit
Carry (DC), and Zero (Z) bits in the STATUS register. The C and DC bits operate as a borrow bit
and a digit borrow out bit, respectively, in subtraction. See the SUBLW and SUBWF instructions for
examples.
Literal Instructions
d = '0' or
W Register
(from instruction word)
8
ALU
8-bit literal
8
Section 5. CPU and ALU
d bit, or from instruction
d = '1'
8
8
8
8-bit register value
(from direct or indirect
address of instruction)
Register
Registers
Function
Purpose
General
Special
(SFR’s)
(GPR)
File
RAM
and
DS31005A-page 5-5
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