PIC16F627-04/SO Microchip Technology, PIC16F627-04/SO Datasheet - Page 91

• Manufacturer Part Number: PIC16F627-04/SO
• Description: IC MCU FLASH 1KX14 COMP 18SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F627-04/SO

• Core Size: 8-Bit
• Program Memory Size: 1.75KB (1K x 14)
• Core Processor: PIC
• Speed: 4MHz
• Connectivity: UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 224 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 18-SOIC (7.5mm Width)
• Controller Family/series: PIC16F
• No. Of I/o's: 16
• Eeprom Memory Size: 128Byte
• Ram Memory Size: 224Byte
• Cpu Speed: 4MHz
• No. Of Timers: 3
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 224 B
• Interface Type: SCI, USART
• Maximum Clock Frequency: 4 MHz
• Number Of Programmable I/os: 16
• Number Of Timers: 3
• Operating Supply Voltage: 3 V to 5.5 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163014, DM164120-4
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT18SO-1 - SOCKET TRANSITION 18SOIC 300MILAC164010 - MODULE SKT PROMATEII DIP/SOIC
• Data Converters: -
• Lead Free Status / Rohs Status: Details

13.3
To read a data memory location, the user must write the
address to the EEADR register and then set control bit
RD (EECON1<0>). The data is available, in the very
next cycle, in the EEDATA register; therefore it can be
read in the next instruction. EEDATA will hold this value
until another read or until it is written to by the user
(during a write operation).
EXAMPLE 13-1:
13.4
To write an EEPROM data location, the user must first
write the address to the EEADR register and the data
to the EEDATA register. Then the user must follow a
specific sequence to initiate the write for each byte.
EXAMPLE 13-2:
The write will not initiate if the above sequence is not
exactly followed (write 55h to EECON2, write AAh to
EECON2, then set WR bit) for each byte. We strongly
recommend that interrupts be disabled during this
code segment. A cycle count is executed during the
required sequence. Any number that is not equal to the
required cycles to execute the required sequence will
cause the data not to be written into the EEPROM.
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.
 2003 Microchip Technology Inc.
MOVWF
BSF
MOVLW
BSF
MOVF
BCF
BSF
BSF
BCF
MOVLW
MOVWF
MOVLW
MOVWF
BSF
BSF
READING THE EEPROM DATA
MEMORY
WRITING TO THE EEPROM DATA
MEMORY
STATUS, RP0
CONFIG_ADDR
EEADR
EECON1, RD
EEDATA, W
STATUS, RP0
STATUS, RP0
EECON1, WREN
INTCON, GIE
55h
EECON2
AAh
EECON2
EECON1,WR
INTCON, GIE
DATA EEPROM READ
DATA EEPROM WRITE
; Bank 1
;
; Address to read
; EE Read
; W = EEDATA
; Bank 0
; Bank 1
; Enable write
; Disable INTs.
;
; Write 55h
;
; Write AAh
; Set WR bit
; begin write
; Enable INTs
.
Preliminary
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. The EEIF bit in the
PIR1 registers must be cleared by software.
13.5
Depending on the application, good programming
practice may dictate that the value written to the Data
EEPROM should be verified (Example 13-3) to the
desired value to be written. This should be used in
applications where an EEPROM bit will be stressed
near the specification limit.
EXAMPLE 13-3:
;
; Is the value written (in W reg) and
; read (in EEDATA) the same?
;
13.6
There are conditions when the device may not want to
write to the data EEPROM memory. To protect against
spurious EEPROM writes, various mechanisms have
been built in. On power-up, WREN is cleared. Also, the
Power-up
EEPROM write.
The write initiate sequence, and the WREN bit together
help prevent an accidental write during brown-out,
power glitch, or software malfunction.
13.7
When the device is code protected, the CPU is able to
read and write unscrambled data to the Data
EEPROM.
BSF
MOVF
BSF
SUBWF EEDATA, W
BCF
BTFSS STATUS, Z
GOTO
:
:
WRITE VERIFY
PROTECTION AGAINST
SPURIOUS WRITE
DATA EEPROM OPERATION
DURING CODE PROTECT
STATUS, RP0
STATUS, RP0
EEDATA, W
EECON1, RD
WRITE_ERR
Timer
(72
WRITE VERIFY
PIC16F62X
; Bank 1
; Read the
; value written
;
; Bank0
; Is difference 0?
; NO, Write error
; YES, Good write
; Continue program
ms
duration)
DS40300C-page 89
prevents