PIC16F877A-I/P Microchip Technology, PIC16F877A-I/P Datasheet - Page 8

• Manufacturer Part Number: PIC16F877A-I/P
• Description: IC MCU FLASH 8KX14 EE 40DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F877A-I/P

• Program Memory Type: FLASH
• Program Memory Size: 14KB (8K x 14)
• Package / Case: 40-DIP (0.600", 15.24mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Eeprom Size: 256 x 8
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 368 B
• Interface Type: CCP/I2C/MSSP/SPI/USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 33
• Number Of Timers: 3
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163022, DV164120
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 444-1001 - DEMO BOARD FOR PICMICRO MCU
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: PIC16F877AI/P

PIC16F87XA
2.5
Depending on the state of the code protection bits, pro-
gram and data memory will be erased using different
methods. The first two commands are used when both
program and data memories are not code-protected.
The third command is used when either memory is
code-protected, or if you want to also erase the fuse
locations, including the code-protect bits. A device pro-
grammer should determine the state of the code pro-
tection bits and then apply the proper command to
erase the desired memory.
2.5.1
When both program and data memories are not
code-protected, they must be individually erased using
the following commands. The only way that both mem-
ories are erased using a single command is if code pro-
tection is enabled for one of the memories. These
commands do not erase the configuration word or ID
locations.
2.5.1.1
When this command is performed, and is followed by
a ‘Begin Erase/Programming’ command, the entire
program memory will be erased.
If the address is pointing to user memory, only the user
memory will be erased.
If the address is pointing to the test program memory
(2000h - 201Fh), then both the user memory and the
test memory will be erased. The configuration word
will not be erased, even if the address is pointing to
location 2007h.
Previously, a load data with 0FFh command was rec-
ommended before any Bulk Erase. On these devices,
this will not be required.
The Bulk Erase command is disabled when the CP bit
is programmed to ‘0’ enabling code-protect.
A timing diagram for this command is shown in
Figure 6-8.
2.5.1.2
When this command is performed, and is followed by
a ‘Begin Erase/Programming’ command, the entire
data memory will be erased.
The Bulk Erase Data command is disabled when the
CPD bit is programmed to ‘0’ enabling protected data
memory. A timing diagram for this command is shown
in Figure 6-9.
DS39589C-page 8
Note:
Erasing Program and Data
Memory
All Bulk Erase operations must take place
at the 4.5V to 5.5V V
ERASING NON-CODE PROTECTED
PROGRAM AND DATA MEMORY
Bulk Erase Program Memory
Bulk Erase Data Memory
DD
range.
Advance Information
2.5.1.3
This command, when performed, will erase the pro-
gram memory, EE data memory, and all of the fuse
locations, including the code protection bits. All
on-chip Flash and EEPROM memory is erased,
regardless of the address contained in the PC.
When a Chip Erase command is issued and the PC
points to (0000h - 1FFFh), the configuration word and
the user program memory will be erased, but not the
test row (see Section 2.5.2.1). Chip Erase can also be
used to erase code-protected memory, as described in
Section 2.5.2.
This command will also erase the code-protect and
code-protect data fuses if they are programmed. This
is the only command that allows a user to erase the
code-protect fuses.
The Chip Erase is internally self-timed to ensure that
all program and data memory is erased before the
code-protect bits are erased. A timing diagram for this
command is shown in Figure 6-10.
2.5.2
For the PIC16F87XA devices, once code protection is
enabled, all protected program and data memory loca-
tions read all ‘0’s and further programming is disabled.
The ID locations and configuration word read out
unscrambled and can be reprogrammed normally. The
only command to erase a code-protected PIC16F87XA
device is the Chip Erase. This erases program mem-
ory, data memory, configuration bits and ID locations.
Since all data within the program and data memory
will be erased when this command is executed, the
security of the data or code is not compromised.
2.5.2.1
This command, when performed, will erase the pro-
gram memory, data EEPROM, and all of the fuse loca-
tions, including the code protection bits, code-protect
fuses, and code-protect data fuses. All on-chip Flash
and EEPROM memory is erased, regardless of the
address contained in the PC.
If the PC points to user memory, the test row (2000h
through 201Fh) is not erased with a Chip Erase com-
mand, except for the configuration word (at 2007h). If
the test row is to be completely erased, the address in
the PC must point to configuration memory.
When the PC points to 2000h - 201Fh, the configura-
tion word, test program memory, and the user program
memory will all be erased with a Chip Erase command.
This allows the user to erase all program and configu-
ration content, including the code-protect bits, without
compromising the user ID bits (2000h through 2004h),
or any pass codes stored in the test row.
Note:
The Chip Erase operation must take place
at the 4.5V to 5.5V V
ERASING CODE PROTECTED
MEMORY
Chip Erase
Chip Erase
 2010 Microchip Technology Inc.
DD
range.