PIC24FJ64GA004-I/ML Microchip Technology, PIC24FJ64GA004-I/ML Datasheet - Page 11

• Manufacturer Part Number: PIC24FJ64GA004-I/ML
• Description: IC PIC MCU FLASH 21KX24 44QFN
• Manufacturer: Microchip Technology
• Series: PIC® 24Fr

Specifications of PIC24FJ64GA004-I/ML

• Program Memory Type: FLASH
• Program Memory Size: 64KB (22K x 24)
• Package / Case: 44-QFN
• Core Processor: PIC
• Core Size: 16-Bit
• Speed: 32MHz
• Connectivity: I²C, PMP, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 35
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC24FJ
• Core: PIC
• Data Bus Width: 16 bit
• Data Ram Size: 8 KB
• Interface Type: I2C/IrDA/SPI/UART
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 35
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52713-733, 52714-737, 53276-922, EWDSPIC
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, DM240011, DM300027, DV164033, MA240013, AC164127, DM240002
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 13-ch x 10-bit
• Controller Family/series: PIC24
• No. Of I/o's: 35
• Ram Memory Size: 8KB
• Cpu Speed: 32MHz
• No. Of Timers: 5
• Embedded Interface Type: I2C, SPI, UART
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 876-1004 - PIC24 BREAKOUT BOARDDM240011 - KIT STARTER MPLAB FOR PIC24F MCUAC162088 - HEADER MPLAB ICD2 24FJ64GA004 28AC164336 - MODULE SOCKET FOR PM3 28/44QFNDV164033 - KIT START EXPLORER 16 MPLAB ICD2
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

© 2006 Microchip Technology Inc.
Section 30. Programmable Cyclic Redundancy Check (CRC)
30.7.3
For 5-bit or 7-bit polynomials, the CRC module will calculate the checksum taking into account
the 5 or 7 Least Significant bits of a byte, respectively. In the case of 5 bits of data, a byte should
contain the 5 bits of data in its 5 Least Significant bits; the Most Significant 3 bits of the byte may
be programmed as zeros. In case of a 7-bit calculation, a byte should contain the 7 bits of data
in its 7 Least Significant bits; the Most Significant bit of a byte may be programmed as zero. Refer
to Section 30.5.2.1 “FIFO to CRC Calculator” for more details.
After forming the bytes from a message stream, the same steps as explained in Section 30.7.2
“8-Bit Polynomial” can be applied. For the polynomial length (PLEN3:PLEN0), use values of 04h
or 06h for 5-bit and 7-bit polynomials, respectively. A suitable 5-bit or 7-bit generator polynomial
may be programmed in the CRCXOR register.
30.7.4
The recommended procedure to calculate a CRC with a 16-bit polynomial is as follows:
1.
2.
3.
4.
5.
6.
7.
8.
Note:
Program PLEN3:PLEN0 bits (CRCCON<3:0>) = 0Fh.
Program a value to CRCXOR (e.g., CRCXOR = 8005h).
Program a value in CRCWDAT:
• 0000h (for the start of a new calculation), or
• the previously calculated partial result (for part of the whole message stream).
If the CRCFUL bit is not set and if all the data words of the message stream are not written
into the FIFO, then write a data word to the CRCDAT register.
If the CRCFUL bit is not set and if all the data words of the message stream are already
written into the FIFO, then write a word of 0000h in CRCDAT and set a software flag in the
application using the CRC (i.e., FINAL_CALCULATION).
If the CRCFUL bit or the software FINAL_CALCULATION flag is set, then start CRC by
setting the CRCGO bit.
When CRCMPT is set, then clear the CRCGO bit and read the result byte from the
CRCWDAT register.
For a partial result (CRC calculation is done but the FINAL_CALCULATION flag is not set),
pass the partial result to the next calculation process.
5-Bit or 7-Bit Polynomials
16-Bit Polynomials
If the length of the polynomial is 16 bits, the CRC module expects an integer multiple
of 16 bits in the FIFO
Advance Information
DS39714A-page 30-11
30