upd70f3402 Renesas Electronics Corporation., upd70f3402 Datasheet - Page 533

• Manufacturer Part Number: upd70f3402
• Description: 32-/16-bit Single-chip Microcontroller With Can Interface
• Manufacturer: Renesas Electronics Corporation.

Remark:
Remark:
<4> Data field
The data field contains the amount of data (byte units) set by the control field. Up to 8 units of data
can be set.
<5> CRC field
The CRC field is a 16-bit field that is used to check for errors in transmit data.
• The polynomial P(X) used to generate the 15-bit CRC sequence is expressed as follows.
• Transmitting node: Transmits the CRC sequence calculated from the data (before bit stuffing)
• Receiving node:
P(X) = X
D: Dominant = 0
R: Recessive = 1
D: Dominant = 0
R: Recessive = 1
R
D
(Control field)
(Data field or control field)
15
R
D
+ X
14
+ X
in the start of frame, arbitration field, control field, and data field.
Compares the CRC sequence calculated using data bits that exclude the
stuffing bits in the receive data with the CRC sequence in the CRC field. If
the two CRC sequences do not match, the node issues an error frame.
MSB
10
User’s Manual U16702EE3V2UD00
+ X
(8 bits)
Data 0
8
Chapter 16 FCAN Controller
→
+ X
Figure 16-10: CRC Field
Figure 16-9: Data Field
7
+ X
LSB
4
+ X
Data field
CRC sequence
3
+ 1
(15 bits)
CRC field
MSB
(8 bits)
Data 7
CRC delimiter
→
(1 bit)
LSB
(ACK field)
(CRC field)
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