PIC16F1826-I/MQ Microchip Technology, PIC16F1826-I/MQ Datasheet - Page 109

• 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

11.1.2
To read a data memory location, the user must write the
address to the EEADRL register, clear the EEPGD and
CFGS control bits of the EECON1 register, and then
set control bit RD. The data is available at the very next
cycle, in the EEDATL register; therefore, it can be read
in the next instruction. EEDATL will hold this value until
another read or until it is written to by the user (during
a write operation).
EXAMPLE 11-1:
EXAMPLE 11-2:
© 2009 Microchip Technology Inc.
BANKSEL EEADRL
MOVLW
MOVWF
BCF
BCF
BSF
MOVF
Note:
BANKSEL EEADRL
MOVLW
MOVWF
MOVLW
MOVWF
BCF
BCF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BCF
BTFSC
GOTO
BSF
DATA_EE_ADDR ;
EEADRL
EECON1, CFGS ;Deselect Config space
EECON1, EEPGD;Point to DATA memory
EECON1, RD
EEDATL, W
READING THE DATA EEPROM
MEMORY
Data EEPROM can be read regardless of
the setting of the CPD bit.
DATA_EE_ADDR
EEADRL
DATA_EE_DATA
EEDATL
EECON1, CFGS
EECON1, EEPGD
EECON1, WREN
INTCON, GIE
55h
EECON2
0AAh
EECON2
EECON1, WR
INTCON, GIE
EECON1, WREN
EECON1, WR
$-2
DATA EEPROM READ
DATA EEPROM WRITE
;
;Data Memory
;Address to read
;EE Read
;W = EEDATL
;
;
;Data Memory Address to write
;
;Data Memory Value to write
;Deselect Configuration space
;Point to DATA memory
;Enable writes
;Disable INTs.
;
;Write 55h
;
;Write AAh
;Set WR bit to begin write
;Enable interrupts
;Disable writes
;Wait for write to complete
;Done
Preliminary
11.1.3
To write an EEPROM data location, the user must first
write the address to the EEADRL register and the data
to the EEDATL register. Then the user must follow a
specific sequence to initiate the write for each byte.
The write will not initiate if the above sequence is not
followed exactly (write 55h to EECON2, write AAh to
EECON2, then set WR bit) for each byte. Interrupts
should be disabled during this code segment.
Additionally, the WREN bit in EECON1 must be set to
enable write. This mechanism prevents accidental
writes to data EEPROM due to errant (unexpected)
code execution (i.e., lost programs). The user should
keep the WREN bit clear at all times, except when
updating EEPROM. The WREN bit is not cleared
by hardware.
After a write sequence has been initiated, clearing the
WREN bit will not affect this write cycle. The WR bit will
be inhibited from being set unless the WREN bit is set.
At the completion of the write cycle, the WR bit is
cleared in hardware and the EE Write Complete
Interrupt Flag bit (EEIF) is set. The user can either
enable this interrupt or poll this bit. EEIF must be
cleared by software.
PIC16F/LF1826/27
WRITING TO THE DATA EEPROM
MEMORY
DS41391B-page 109