Intel 8XC196NT 87C196CB SUPPLEMENT -6. Standard Message Frame, 7. Extended Message Frame

Models: 8XC196NT 87C196CB

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87C196CB SUPPLEMENT

87C196CB SUPPLEMENT

Table 7-6. Standard Message Frame

Field

Description

Bit Count

 

 

 

SOF

Start-of-frame. A dominant (0) bit marks the beginning of a message frame.

1

 

 

 

 

11-bit message identifier.

 

Arbitration

 

12

RTR. Remote transmission request. Dominant (0) for data frames; recessive (1)

 

 

 

for remote frames.

 

 

 

 

 

IDE. Identifier extension bit; always dominant (0).

 

 

 

 

Control

r0. Reserved bit; always dominant (0).

6

 

 

 

 

DLC. Data length code. A 4-bit code indicating the number of data bytes (0–8).

 

 

 

 

Data

Data. 1 to 8 bytes for data frames; 0 bytes for remote frames.

0–64

 

 

 

CRC

CRC code. A 15-bit CRC code plus a recessive (1) delimiter bit.

16

 

 

 

Ack

Acknowledgment. A dominant (0) bit sent by nodes receiving the frame plus a

2

 

recessive (1) delimiter bit.

 

 

 

 

 

End of frame

7 recessive (1) bits mark the end of a frame.

7

 

 

 

 

Minimum standard message frame length (bits)

44–108

 

 

 

Table 7-7. Extended Message Frame

Field

Description

Bit Count

 

 

 

SOF

Start-of-frame. A dominant (0) bit marks the beginning of a message frame.

1

 

 

 

 

11 bits of the 29-bit message identifier.

 

 

 

 

 

SRR. Substitute remote transmission request; always recessive (1).

 

 

 

 

Arbitration

IDE. Identifier extension bit; always recessive (1).

32

 

 

 

 

18 bits of the 29-bit message identifier.

 

 

 

 

 

RTR. Remote transmission request; always recessive (1).

 

 

 

 

 

r0. Reserved bit; always dominant (0).

 

 

 

 

Control

r1. Reserved bit; always dominant (0).

6

 

 

 

 

DLC. Data length code. A 4-bit code indicating the number of data bytes (0–8).

 

 

 

 

Data

Data. 1 to 8 bytes for data frames; 0 bytes for remote frames.

0–64

 

 

 

CRC

CRC code. A 15-bit CRC code plus a recessive (1) delimiter bit.

16

 

 

 

Ack

Acknowledgment. A dominant (0) bit sent by nodes receiving the frame plus a

2

 

recessive (1) delimiter bit.

 

 

 

 

 

End of frame

7 recessive (1) bits mark the end of a frame.

7

 

 

 

 

Minimum extended message frame length (bits)

64–128

 

 

 

7-8

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Intel 8XC196NT user manual 87C196CB SUPPLEMENT -6. Standard Message Frame, 7. Extended Message Frame