19.10.3 Storage of Messages with Less Than 8 Data

19.10.4 Storage of Extended Messages

 

 

 

Bytes

 

 

 

 

 

 

 

If the IDE bit is set, the buffer handles extended frames. The

 

 

 

 

 

 

 

 

 

The data bytes that are not used for data transfer are “don’t

storage of the extended ID follows the descriptions in

cares”. If the object is transmitted, the data within these

Table 55. The SRR bit is at the bit position of the RTR bit for

bytes will be ignored. If the object is received, the data with-

standard frame and needs to be transmitted as 1.

 

in these bytes will be overwritten with invalid data.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 55 Extended Messages with 8 Data Bytes

 

 

 

 

 

 

 

Address

Buffer

15

14

13

12

 

11

10

9

8

 

7

6

5

4

3

 

2

1

0

Register

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0XEh

ID1

 

 

 

 

 

ID[28:18]

 

 

 

 

 

SRR

IDE

 

 

ID17:15]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0XCh

ID0

 

 

 

 

 

 

 

 

ID[14:0]

 

 

 

 

 

 

 

 

RTR

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0XAh

DATA0

 

 

 

Data1[7:0]

 

 

 

 

 

 

 

Data2[7:0]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0X8h

DATA1

 

 

 

Data3[7:0]

 

 

 

 

 

 

 

Data4[7:0]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0X6h

DATA2

 

 

 

Data5[7:0]

 

 

 

 

 

 

 

Data6[7:0]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0X4h

DATA3

 

 

 

Data7[7:0]

 

 

 

 

 

 

 

Data8[7:0]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0X2h

TSTP

 

 

 

 

 

 

 

 

TSTP[15:0]

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0E F0X0h

CNSTAT

 

DLC

 

 

 

Reserved

 

 

 

PRI

 

 

 

 

 

ST

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SRR

The Substitute Remote Request bit replaces

 

 

 

 

 

 

 

 

 

 

 

 

 

the RTR bit used in standard frames at this bit

 

 

 

 

 

 

 

 

 

 

 

 

 

position. The SRR bit needs to be set by soft-

 

 

 

 

 

 

 

 

 

 

 

 

 

ware if the buffer is configured to transmit a

 

 

 

 

 

 

 

 

 

 

 

 

 

message with an extended identifier. It will be

 

 

 

 

 

 

 

 

 

 

 

 

 

received as monitored on the CAN bus.

 

 

 

 

 

 

 

 

 

 

 

 

 

IDE

The Identifier Extension bit determines wheth-

 

 

 

 

 

 

 

 

 

 

 

 

 

er the message is a standard frame or an ex-

 

 

 

 

 

 

 

 

 

 

 

 

 

tended frame.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0 – Message is a standard frame using 11

 

 

 

 

 

 

 

 

 

 

 

 

 

identifier bits.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1 – Message is an extended frame.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RTR

The Remote Transmission Request bit indi-

 

 

 

 

 

 

 

 

 

 

 

 

 

cates whether the message is a data frame or

 

 

 

 

 

 

 

 

 

 

 

 

 

a remote frame.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0 – Message is a data frame.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1 – Message is a remote frame.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ID

The ID field is used to build the 29-bit identifier

 

 

 

 

 

 

 

 

 

 

 

 

 

of an extended frame.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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131

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National CP3BT26 manual Extended Messages with 8 Data Bytes Address Buffer Register, Cnstat DLC, Pri Srr