PIC24FJ128GA106-I/PT Microchip Technology, PIC24FJ128GA106-I/PT Datasheet - Page 170

• Manufacturer Part Number: PIC24FJ128GA106-I/PT
• Description: IC PIC MCU FLASH 64TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 24Fr

Specifications of PIC24FJ128GA106-I/PT

• Program Memory Type: FLASH
• Program Memory Size: 128KB (43K x 24)
• Package / Case: 64-TFQFP
• 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: 53
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC24FJ
• Core: PIC
• Data Bus Width: 16 bit
• Data Ram Size: 16 KB
• Interface Type: I2C/SPI/UART
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 53
• 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, DM240001
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 16-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 876-1004 - PIC24 BREAKOUT BOARDMA240015 - BOARD MCV PIM FOR 24F256GA
• Eeprom Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC24FJ128GA010 FAMILY
FIGURE 19-2:
19.3
19.3.1
To start serial shifting, a ‘1’ must be written to the
CRCGO bit.
The module incorporates a FIFO that is 8 deep when
PLEN (PLEN<3:0>) > 7, and 16 deep otherwise. The
data for which the CRC is to be calculated must first be
written into the FIFO. The smallest data element that
can be written into the FIFO is one byte. For example,
if PLEN = 5, then the size of the data is PLEN + 1 = 6.
The data must be written as follows:
Once data is written into the CRCWDAT MSb (as
defined
(VWORD<4:0>) increments by one. The serial shifter
starts shifting data into the CRC engine when
CRCGO = 1 and VWORD > 0. When the MSb is
shifted out, VWORD decrements by one. The serial
shifter continues shifting until the VWORD reaches 0.
Therefore, for a given value of PLEN, it will take
(PLEN + 1) * VWORD number of clock cycles to
complete the CRC calculations.
When VWORD reaches 8 (or 16), the CRCFUL bit will
be set. When VWORD reaches 0, the CRCMPT bit will
be set.
DS39747D-page 168
SDOx
XOR
User Interface
by
DATA INTERFACE
D
data[5:0] = crc_input[5:0]
BIT 0
p_clk
PLEN),
Q
data[7:6] = ‘bxx
CRC GENERATOR RECONFIGURED FOR x
the
D
p_clk
BIT 4
value
Q
of
VWORD
Preliminary
D
BIT 5
p_clk
Q
To continually feed data into the CRC engine, the rec-
ommended mode of operation is to initially “prime” the
FIFO with a sufficient number of words so no interrupt
is generated before the next word can be written. Once
that is done, start the CRC by setting the CRCGO bit to
‘1’. From that point onward, the VWORD bits should be
polled. If they read less than 8 or 16, another word can
be written into the FIFO.
To empty words already written into a FIFO, the
CRCGO bit must be set to ‘1’ and the CRC shifter
allowed to run until the CRCMPT bit is set.
Also, to get the correct CRC reading, it will be
necessary to wait for the CRCMPT bit to go high before
reading the CRCWDAT register.
If a word is written when the CRCFUL bit is set, the
VWORD Pointer will roll over to 0. The hardware will
then behave as if the FIFO is empty. However, the con-
dition to generate an interrupt will not be met; therefore,
no interrupt will be generated (see Section 19.3.2
“Interrupt Operation”).
At least one instruction cycle must pass after a write to
CRCWDAT before a read of the VWORD bits is done.
19.3.2
When VWORD4:VWORD0 make a transition from a
value of ‘1’ to ‘0’, an interrupt will be generated.
16
INTERRUPT OPERATION
+ x
12
CRC Read Bus
D
BIT 12
p_clk
+ x
Q
5
© 2007 Microchip Technology Inc.
+ 1
CRC Write Bus
BIT 15
D
p_clk
Q