CP3BT26 Datasheet, PDF (130/278 Pages) National Semiconductor (TI) – Reprogrammable Connectivity Processor with Bluetooth-R, USB, and CAN Interfaces

PRI
The Transmit Priority Code field holds the Note: The maximum number of data bytes received/trans-
software-defined transmit priority code for the mitted is 8, even if the DLC field is set to a value greater than
message buffer.
8. Therefore, if the data length code is greater or equal to
DLC
The Data Length Code field determines the eight bytes, the DLC field is ignored.
number of data bytes within a received/trans-
mitted frame. For transmission, these bits ^{19.10.2 Storage of Standard Messages}
need to be set according to the number of ^{During the processing of standard frames, the Extended-}
data bytes to be transmitted. For reception, ^{Identifier (IDE) bit is clear. The ID1[3:0] and ID0[15:0] bits}
these bits indicate the number of valid re- are “don’t care” bits. A standard frame with eight data bytes
ceived data bytes available in the message ^{is shown in Table 54.}
buffer. Table 53 shows the possible bit combi- _IDE
nations for DLC3:0 for data lengths from 0 to
8 bytes.
The Identifier Extension bit determines wheth-
er the message is a standard frame or an ex-
tended frame.
Table 53 Data Length Coding
0 – Message is a standard frame using 11
identifier bits.
1 – Message is an extended frame.
DLC
Number of Data Bytes _RTR
The Remote Transmission Request bit indi-
0000
0
cates whether the message is a data frame or
a remote frame.
0001
1
0 – Message is a data frame.
1 – Message is a remote frame.
0010
2
ID
The ID field is used for the 11 standard frame
identifier bits.
0011
3
0100
4
0101
5
0110
6
0111
7
1000
8
Table 54 Standard Frame with 8 Data Bytes
Address
Buffer
Register
15
0E F0XEh
0E F0XCh
0E F0XAh
ID1
ID0
DATA0
0E F0X8h
0E F0X6h
0E F0X4h
DATA1
DATA2
DATA3
0E F0X2h TSTP
0E F0X0h CNSTAT
14 13 12 11 10 9 8 7 6 5
ID[10:0]
Don’t Care
Data1[7:0]
Data3[7:0]
Data5[7:0]
Data7[7:0]
TSTP[15:0]
DLC
Reserved
PRI
43
RTR IDE
Data2[7:0]
Data4[7:0]
Data6[7:0]
Data8[7:0]
210
Don’t Care
ST
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