Datasheet

msCAN12 Controller
M68HC12B Family Data Sheet, Rev. 9.1
260 Freescale Semiconductor
RTR — Remote Transmission Request Flag
This flag reflects the status of the remote transmission request bit in the CAN frame. In case of a
receive buffer, it indicates the status of the received frame and supports the transmission of an
answering frame in software. In case of a transmit buffer, this flag defines the setting of the RTR bit to
be sent.
0 = Data frame
1 = Remote frame
16.11.3 Data Length Register
The data length register (DLR) keeps the data length field of the CAN frame.
DLC3–DLC0 — Data Length Code Bits
The data length code contains the number of bytes (data byte count) of the respective message. At
transmission of a remote frame, the data length code is transmitted as programmed while the number
of transmitted bytes is always 0. The data byte count ranges from 0 to 8 for a data frame. Table 16-4
shows the effect of setting the DLC bits.
Address: $01xC
Bit 7654321Bit 0
Read:
DLC3 DLC2 DLC1 DLC0
Write:
Reset: Undefined out of reset
= Unimplemented
Note: x is 4, 5, 6, or 7 depending on which buffer, RxFG, Tx0, Tx1, or Tx3, respectively.
Figure 16-13. Data Length Register (DLR)
Table 16-4. Data Length Codes
Data Length Code Data
Byte
Count
DLC3 DLC2 DLC1 DLC0
00000
00011
00102
00113
01004
01015
01106
01117
10008