PIC18F4420T-I/PT Microchip Technology, PIC18F4420T-I/PT Datasheet - Page 25

• Manufacturer Part Number: PIC18F4420T-I/PT
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,TQFP,44PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F4420T-I/PT

• Rohs Compliant: YES
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 36
• Program Memory Size: 16KB (8K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 768 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
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

4.2
The verify step involves reading back the code memory
space and comparing it against the copy held in the
programmer’s buffer. Memory reads occur a single byte
at a time, so two bytes must be read to compare
against the word in the programmer’s buffer. Refer to
Section 4.1 “Read Code Memory, ID Locations and
Configuration Bits”
reading code memory.
FIGURE 4-2:
 2010 Microchip Technology Inc.
Verify Code Memory and ID
Locations
No
with Post-Increment
with Post-Increment
Set TBLPTR = 0
Read High Byte
Read Low Byte
Word = Expect
code memory
verified?
Data?
Start
Does
VERIFY CODE MEMORY FLOW
for implementation details of
All
Yes
Yes
No
Failure,
Report
Error
PIC18F2XXX/4XXX FAMILY
Increment
Pointer
The Table Pointer must be manually set to 200000h
(base address of the ID locations) once the code
memory has been verified. The post-increment feature
of the Table Read 4-bit command may not be used to
increment the Table Pointer beyond the code memory
space. In a 64-Kbyte device, for example, a
post-increment read of address, FFFFh, will wrap the
Table Pointer back to 000000h, rather than point to the
unimplemented address, 010000h.
No
Set TBLPTR = 200000h
with Post-Increment
with Post-Increment
Read High Byte
Read Low Byte
Word = Expect
ID locations
verified?
Data?
Done
Does
All
Yes
Yes
No
DS39622L-page 25
Failure,
Report
Error