PIC18F452-I/P Microchip Technology, PIC18F452-I/P Datasheet - Page 14

• Manufacturer Part Number: PIC18F452-I/P
• Description: IC MCU FLASH 16KX16 EE 40DIP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F452-I/P

• Program Memory Type: FLASH
• Program Memory Size: 32KB (16K x 16)
• Package / Case: 40-DIP (0.600", 15.24mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 34
• Eeprom Size: 256 x 8
• Ram Size: 1.5K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 1.5 KB
• Interface Type: MSSP/SPI/I2C/PSP/USART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 34
• Number Of Timers: 4
• 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, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, ICE4000, DV164136, DM163022
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Package: 40PDIP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 444-1001 - DEMO BOARD FOR PICMICRO MCUACICE0206 - ADAPTER MPLABICE 40P 600 MIL
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: PIC18F452I/P; Q1176145

PIC18FXX2/XX8
3.2.1
The programming example presented in Section 3.2
utilizes multi-panel programming. This technique
greatly decreases the total amount of time necessary to
completely program a device and is the recommended
method of completely programming a device.
There may be situations, however, where it is advanta-
geous to limit writes to a single panel. In such cases,
the user only needs to disable the multi-panel write
feature of the device by appropriately configuring the
programming control register located at 3C0006h.
The single panel that will be written will automatically
be enabled, based on the value of the Table Pointer.
3.2.2
All of the programming examples up to this point have
assumed that the device is blank prior to programming.
In fact, if the device is not blank, the direction has been
to completely erase the device via a Bulk Erase
operation (see Section 3.1) operation.
It may be the case, however, that the user wishes to
modify only a section of an already programmed
device. In such a situation, erasing the entire device is
not a realistic option.
The minimum amount of data that can be written to the
device is 8 bytes. This is accomplished by placing the
device in Single Panel Write mode (see Section 3.2.1),
loading the 8-byte write buffer for the panel, and then
initiating a write sequence. In this case, however, it is
assumed that the address space to be written already
has data in it (i.e., it is not blank).
DS39576C-page 14
Note:
For single panel programming, the user
must still fill the 8-byte write buffer for the
given panel.
SINGLE PANEL PROGRAMMING
MODIFYING CODE MEMORY
The minimum amount of code memory that may be
erased at a given time is 64 bytes. Again, the device
must be placed in Single Panel Write mode. The
EECON1 register must then be used to erase the
64-byte target space prior to writing the data.
When using the EECON1 register to act on code mem-
ory, the EEPGD bit must be set (EECON1<7> = 1) and
the CFGS bit must be cleared (EECON1<6> = 0). The
WREN bit must be set (EECON1<2> = 1) to enable
writes of any sort (e.g., erases), and this must be done
prior to initiating a write sequence. The FREE bit must
be set (EECON1<4> = 1) in order to erase the program
space being pointed to by the Table Pointer. The erase
sequence is initiated by the setting the WR bit
(EECON1<1> = 1). It is strongly recommended that the
WREN bit be set only when absolutely necessary.
To help prevent inadvertent writes when using the
EECON1 register, EECON2 is used to “enable” the WR
bit. This register must be sequentially loaded with 55h
and then, AAh, immediately prior to asserting the WR
bit in order for the write to occur.
The erase will begin on the falling edge of the 4th SCLK
after the WR bit is set.
After the erase sequence terminates, SCLK must still
be held low for the time specified by parameter P10 to
allow high voltage discharge of the memory array.
 2010 Microchip Technology Inc.