PIC18F4320-I/PT Microchip Technology, PIC18F4320-I/PT Datasheet - Page 79

• Manufacturer Part Number: PIC18F4320-I/PT
• Description: IC MCU FLASH 4KX16 A/D 44TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F4320-I/PT

• Core Size: 8-Bit
• Program Memory Size: 8KB (4K x 16)
• Core Processor: PIC
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 36
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Controller Family/series: PIC18
• No. Of I/o's: 36
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 40MHz
• No. Of Timers: 4
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: XLT44PT3 - SOCKET TRAN ICE 44MQFP/TQFPAC164305 - MODULE SKT FOR PM3 44TQFP444-1001 - DEMO BOARD FOR PICMICRO MCUAC164020 - MODULE SKT PROMATEII 44TQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

6.5
The programming block size is 4 words or 8 bytes.
Word or byte programming is not supported.
Table writes are used internally to load the holding reg-
isters needed to program the Flash memory. There are
8 holding registers used by the table writes for
programming.
FIGURE 6-5:
6.5.1
The sequence of events for programming an internal
program memory location should be:
1.
2.
3.
4.
5.
6.
7.
© 2007 Microchip Technology Inc.
TBLPTR = xxxxx0
Read 64 bytes into RAM.
Update data values in RAM as necessary.
Load Table Pointer with address being erased.
Do the row erase procedure (see Section 6.4.1
“Flash Program Memory Erase Sequence”).
Load Table Pointer with address of first byte
being written.
Write the first 8 bytes into the holding registers
with auto-increment.
Set the EECON1 register for the write operation:
• set EEPGD bit to point to program
• clear the CFGS bit to access program
• set WREN bit to enable byte writes.
memory;
memory;
Writing to Flash Program Memory
FLASH PROGRAM MEMORY WRITE
SEQUENCE
Holding Register
8
TABLE WRITES TO FLASH PROGRAM MEMORY
TBLPTR = xxxxx1
Holding Register
PIC18F2220/2320/4220/4320
8
Program Memory
Write Register
TBLPTR = xxxxx2
TABLAT
Since the Table Latch (TABLAT) is only a single byte,
the TBLWT instruction has to be executed 8 times for
each programming operation. All of the table write
operations will essentially be short writes because only
the holding registers are written. At the end of updating
8 registers, the EECON1 register must be written to, to
start the programming operation with a long write.
The long write is necessary for programming the inter-
nal Flash. Instruction execution is halted while in a long
write cycle. The long write will be terminated by the
internal programming timer.
8.
9.
10. Write AAh to EECON2.
11. Set the WR bit. This will begin the write cycle.
12. The CPU will stall for duration of the write (about
13. Execute a NOP.
14. Re-enable interrupts.
15. Repeat steps 6-14 seven times, to write 64
16. Verify the memory (table read).
This procedure will require about 18 ms to update one
row of 64 bytes of memory. An example of the required
code is given in Example 6-3.
Holding Register
Disable interrupts.
Write 55h to EECON2.
2 ms using internal timer).
bytes.
8
TBLPTR = xxxxx7
Holding Register
DS39599G-page 77
8