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19.10.5 Storage of Remote Messages
During remote frame transfer, the buffer registers DATA0–
DATA3 are "don't cares". If a remote frame is transmitted,
the contents of these registers are ignored. If a remote
Buffer
Address
Register
0E F0XEh
ID1
0E F0XCh
ID0
0E F0XAh
DATA0
0E F0X8h
DATA1
0E F0X6h
DATA2
0E F0X4h
DATA3
0E F0X2h
TSTP
0E F0X0h
CNSTAT
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.
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. The ID[28:18] field is
used for the 11 standard frame identifier bits.
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Table 56 Extended Remote Frame
15
14
13
12
11
DLC
frame is received, the contents of these registers will be
overwritten with invalid data. The structure of a message
buffer set up for a remote frame with extended identifier is
shown in Table 56.
10
9
8
7
ID[28:18]
ID[14:0]
Don't Care
TSTP
Reserved
132
6
5
4
3
2
SRR IDE
PRI
ST
1
0
ID17:15]
RTR
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