ST STM32F207 Series Reference Manual page 825

RM0033
CAN mailbox data length control and time stamp register (CAN_TDTxR)
(x=0..2)
All bits of this register are write protected when the mailbox is not in empty state.
Address offsets: 0x184, 0x194, 0x1A4
Reset value: 0xXXXX XXXX
31 30 29
rw rw rw
15 14 13
Reserved
Bits 31:16 TIME[15:0]
Bits 15:9 Reserved, must be kept at reset value.
Bit 8 TGT
Bits 7:4 Reserved, must be kept at reset value.
Bits 3:0 DLC[3:0]
28 27 26 25
rw rw rw rw
12 11 10 9
:
Message time stamp
This field contains the 16-bit timer value captured at the SOF transmission.
:
Transmit global time
This bit is active only when the hardware is in the Time Trigger Communication mode,
TTCM bit of the CAN_MCR register is set.
0: Time stamp TIME[15:0] is not sent.
1: Time stamp TIME[15:0] value is sent in the last two data bytes of the 8-byte message:
TIME[7:0] in data byte 7 and TIME[15:8] in data byte 6, replacing the data written in
CAN_TDHxR[31:16] register (DATA6[7:0] and DATA7[7:0]). DLC must be programmed as 8
in order these two bytes to be sent over the CAN bus.
:
Data length code
This field defines the number of data bytes a data frame contains or a remote frame request.
A message can contain from 0 to 8 data bytes, depending on the value in the DLC field.
24 23 22
TIME[15:0]
rw rw rw
8 7 6
TGT
Reserved
rw
RM0033 Rev 9
Controller area network (bxCAN)
21 20 19 18
rw rw rw rw
5 4 3 2
DLC[3:0]
rw rw
17 16
rw rw
1 0
rw rw
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