PIC16F777-I/P Microchip Technology Inc., PIC16F777-I/P Datasheet - Page 29

• Manufacturer Part Number: PIC16F777-I/P
• Description: 40 PIN, 14 KB FLASH, 368 RAM, 36 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F777-I/P

• A/d Inputs: 14-Channel, 10-Bit
• Comparators: 2
• Cpu Speed: 5 MIPS
• Eeprom Memory: 0 Bytes
• Input Output: 36
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 40-pin PDIP
• Programmable Memory: 14K Bytes
• Ram Size: 368 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

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 2-5.
A simple program to clear RAM locations 20h-2Fh
using indirect addressing is shown in Example 2-2.
FIGURE 2-5:
 2002 Microchip Technology Inc.
Bank Select
RP1:RP0
Note 1: For register file map detail, see Figure 2-2.
Indirect Addressing, INDF and FSR
Registers
Location Select
6
Direct Addressing
Data
Memory
DIRECT/INDIRECT ADDRESSING
From Opcode
(1)
00h
7Fh
Bank 0
00
0
80h
FFh
Bank 1
01
100h
17Fh
Bank 2
10
EXAMPLE 2-2:
NEXT
CONTINUE
180h
1FFh
:
Bank 3
11
MOVLW
MOVWF
CLRF
INCF
BTFSS
GOTO
IRP
Bank Select
0x20
FSR
INDF
FSR,F
FSR,4
NEXT
7
INDIRECT ADDRESSING
Indirect Addressing
;initialize pointer
;to RAM
;clear INDF register
;inc pointer
;all done?
;no clear next
;yes continue
PIC16F7X
FSR Register
DS30325B-page 27
Location Select
0