DSPIC33EP128MC504-I/ML Microchip Technology, DSPIC33EP128MC504-I/ML Datasheet - Page 370

• Manufacturer Part Number: DSPIC33EP128MC504-I/ML
• Description: Digital Signal Processors & Controllers - DSP, DSC 16B 128KB FL 16KBR 60MHz 44P OpAmps
• Manufacturer: Microchip Technology
• Type: dsPIC33E/PIC24Er

Specifications of DSPIC33EP128MC504-I/ML

• Rohs: yes
• Core: dsPIC33E
• Data Bus Width: 16 bit
• Program Memory Size: 128 KB
• Data Ram Size: 16 KB
• Maximum Clock Frequency: 7.37 MHz, 32 kHz
• Number Of Programmable I/os: 35
• Number Of Timers: 5 x 16-bit, 2 x 32-bit
• Device Million Instructions Per Second: 70 MIPs
• Operating Supply Voltage: 3 V to 3.6 V
• Maximum Operating Temperature: + 85 C
• Package / Case: TQFP-44
• Mounting Style: SMD/SMT
• Family / Core: dsPIC33E/PIC24E
• Interface Type: CAN, I2C, SPI, UART
• Minimum Operating Temperature: - 40 C
• On-chip Adc: Yes
• Product: DSPs
• Program Memory Type: Flash
• Supply Current: 10 mA

Note that the appropriate positions are set to ‘1’ to
dsPIC33EPXXXGP50X, dsPIC33EPXXXMC20X/50X, AND PIC24EPXXXGP/MC20X
26.1
The CRC module can be programmed for CRC
polynomials of up to the 32nd order, using up to 32 bits.
Polynomial length, which reflects the highest exponent
in the equation, is selected by the PLEN<4:0> bits
(CRCCON2<4:0>).
The CRCXORL and CRCXORH registers control which
exponent terms are included in the equation. Setting a
particular bit includes that exponent term in the
equation; functionally, this includes an XOR operation
on the corresponding bit in the CRC engine. Clearing
the bit disables the XOR.
For example, consider two CRC polynomials, one a 16-
bit equation and the other a 32-bit equation:
To program these polynomials into the CRC generator,
set the register bits as shown in
indicate that they are used in the equation (for example,
X26 and X23). The 0 bit required by the equation is
always XORed; thus, X0 is a don’t care. For a poly-
nomial of length N, it is assumed that the Nth bit will
always be used, regardless of the bit setting. Therefore,
for a polynomial length of 32, there is no 32nd bit in the
CRCxOR register.
TABLE 26-1:
DS70657F-page 370
x32 + x26 + x23 + x22 + x16 + x12 + x11 + x10 + x8 + x7
PLEN<4:0>
X<31:16>
X<15:0>
CRC Control
Bits
Overview
+ x5 + x4 + x2 + x + 1
16 AND 32-BIT POLYNOMIAL
x16 + x12 + x5 + 1
CRC SETUP EXAMPLES FOR
0000 0000
0000 000x
0001 0000
0010 000x
Polynomial
01111
16-bit
and
Bit Values
Table
26-1.
Polynomial
0000 0100
1100 0001
0001 1101
1011 011x
11111
32-bit
26.2
Many useful resources are provided on the main prod-
uct page of the Microchip web site for the devices listed
in this data sheet. This product page, which can be
accessed using this link, contains the latest updates
and additional information.
26.2.1
• Section 27. “Programmable Cyclic Redundancy
• Code Samples
• Application Notes
• Software Libraries
• Webinars
• All related dsPIC33E/PIC24E Family Reference
• Development Tools
Note:
Check (CRC)” (DS70346)
Manuals Sections
Programmable CRC Resources
In the event you are not able to access the
product page using the link above, enter
this URL in your browser:
http://www.microchip.com/wwwproducts/
Devices.aspx?dDocName=en555464
KEY RESOURCES
 2011-2012 Microchip Technology Inc.