msm9225 Oki Semiconductor, msm9225 Datasheet - Page 50

• Manufacturer Part Number: msm9225
• Description: Can Controller Area Network Controller
• Manufacturer: Oki Semiconductor

* In the case of a remote frame, even when the data length code 0, there is no data field.
• The polynominal P(X) that generates the 15-bit CRC is expressed as follows.
• The transmit node transmits a CRC sequence computed from all basic data bits of the start-of-
• The receive node, compares the CRC sequence computed from data bits of the received data
¡ Semiconductor
frame, arbitration field, control field, and data field, without bit stuffing.
(excluding stuff bits) with the CRC sequence in the CRC field. If they do not match, the node
switches to an error frame.
(d) Data field
The data field contains the number of data groups set by the control field. A maximum of 8
data groups can be set.
8 bits form 1 data group. (MSB first)
(e) CRC field
A 15-bit CRC sequence checks for transmission errors.
The CRC field consists of a 15-bit CRC sequence and a 1-bit CRC delimiter.
(Data field, control field)
P(X) = X
R
D
R
D
15
(Control field)
+ X
DLC3
14
0
0
0
1
•
•
+ X
10
Data length code
DLC2
+ X
0
0
1
0
•
•
CRC sequence
Data Length Code Setting
(8 bits)
8
Data
(15 bits)
+ X
CRC field
7
DLC1
+ X
0
0
1
0
•
•
4
+ X
Data field
DLC0
CRC delimiter
3
0
1
1
0
+ 1
•
•
(1 bit)
No. of data bytes
Ack field
(8 bits)
Data
0
1
7
8
•
•
(CRC field)
MSM9225
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