PIC16F1947-I/PT Microchip Technology Inc., PIC16F1947-I/PT Datasheet - Page 23

• Manufacturer Part Number: PIC16F1947-I/PT
• Description: 64 TQFP 10x10x1mm TRAY28KB Flash, 1KB RAM, 256B EEPROM, LCD, 1.8-5.5V
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F1947-I/PT

• A/d Inputs: 17-Channel, 10-Bit
• Comparators: 3
• Cpu Speed: 8 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 54
• Interface: CAN/I2C/SPI/UART/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 64-pin TQFP
• Programmable Memory: 28K Bytes
• Ram Size: 1K Bytes
• Speed: 32 MHz
• Timers: 4-8-bit, 1-16-bit
• Voltage, Range: 1.8-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

3.1.1
There are two methods of accessing constants in pro-
gram memory. The first method is to use tables of
RETLW instructions. The second method is to set an
FSR to point to the program memory.
3.1.1.1
The RETLW instruction can be used to provide access
to tables of constants. The recommended way to create
such a table is shown in
EXAMPLE 3-1:
The BRW instruction makes this type of table very
simple to implement. If your code must remain portable
with previous generations of microcontrollers, then the
BRW instruction is not available so the older table read
method must be used.
 2010 Microchip Technology Inc.
constants
my_function
BRW
RETLW DATA0
RETLW DATA1
RETLW DATA2
RETLW DATA3
;… LOTS OF CODE…
MOVLW
CALL constants
;… THE CONSTANT IS IN W
READING PROGRAM MEMORY AS
DATA
RETLW Instruction
DATA_INDEX
RETLW INSTRUCTION
Example
;Add Index in W to
;program counter to
;select data
;Index0 data
;Index1 data
3-1.
Preliminary
PIC16F/LF1946/47
DS41414B-page 23