PIC16F1826-I/MQ Microchip Technology, PIC16F1826-I/MQ Datasheet - Page 21

• Manufacturer Part Number: PIC16F1826-I/MQ
• Description: IC, 8BIT MCU, PIC16F, 32MHZ, QFN-28
• Manufacturer: Microchip Technology

Specifications of PIC16F1826-I/MQ

• Controller Family/series: PIC16F
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 256Byte
• Cpu Speed: 32MHz
• No. Of Timers: 3
• Interface: EUSART, I2C, SPI
• Core Size: 8 Bit
• Program Memory Size: 2kWords
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

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.
EXAMPLE 3-1:
The BRW instruction makes this type of table very sim-
ple 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.
© 2009 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
;Add Index in W to
;program counter to
;select data
;Index0 data
;Index1 data
Preliminary
PIC16F/LF1826/27
DS41391B-page 21