PIC16F876AT-I/SO Microchip Technology, PIC16F876AT-I/SO Datasheet - Page 33

• Manufacturer Part Number: PIC16F876AT-I/SO
• Description: IC MCU CMOS 20MHZ 8K FLSH 28SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F876AT-I/SO

• 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: 22
• 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 5x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Controller Family/series: PIC16F
• No. Of I/o's: 22
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 368Byte
• Cpu Speed: 20MHz
• No. Of Timers: 3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

2.5
The INDF register is not a physical register. Addressing
the INDF register will cause indirect addressing.
Indirect addressing is possible by using the INDF reg-
ister. Any instruction using the INDF register actually
accesses the register pointed to by the File Select Reg-
ister, FSR. Reading the INDF register itself, indirectly
(FSR = 0) will read 00h. Writing to the INDF register
indirectly results in a no operation (although status bits
may be affected). An effective 9-bit address is obtained
by concatenating the 8-bit FSR register and the IRP bit
(Status<7>) as shown in Figure 2-6.
FIGURE 2-6:
 2003 Microchip Technology Inc.
Bank Select
RP1:RP0
Note 1: For register file map detail, see Figure 2-3.
Indirect Addressing, INDF and
FSR Registers
Direct Addressing
Location Select
6
Data
Memory
DIRECT/INDIRECT ADDRESSING
From Opcode
(1)
00h
7Fh
Bank 0
00
0
80h
FFh
Bank 1
01
100h
17Fh
Bank 2
10
A simple program to clear RAM locations 20h-2Fh
using indirect addressing is shown in Example 2-2.
EXAMPLE 2-2:
NEXT
CONTINUE
180h
1FFh
Bank 3
11
MOVLW 0x20
MOVWF FSR
CLRF
INCF
BTFSS FSR,4
GOTO
:
IRP
Bank Select
INDF
FSR,F
NEXT
PIC16F87XA
Indirect Addressing
7
INDIRECT ADDRESSING
;initialize pointer
;to RAM
;clear INDF register
;inc pointer
;all done?
;no clear next
;yes continue
FSR Register
DS39582B-page 31
Location Select
0