GD32A50x User Manual
603
CODE
Meaning
CODE after
transmission
RTR
Description
mailbox automatically becomes an Rx empty mailbox
with the same ID.
0b1110
TANSWE
R
RANSWER
-
This is an intermediate code which is automatically
written to the mailbox by the controller interface when a
matching remote request frame is received. After
transmitting the remote response frame, the mailbox will
automatically return to RANSWER state. The CPU can
also write this code with the same effect. The remote
response frame can be either a data frame or another
remote request frame depending on the RTR bit.
MDES1: Mailbox descriptor word 1
Address offset: 0x84
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
PRIO[2:0]
ID_STD[10:0]
ID_EXD[17:16]
rw
rw
rw
15
14
13
12
11
rw
9
8
7
6
5
4
3
2
1
0
ID_EXD[15:0]
rw
Bits
Fields
Descriptions
31:29
PRIO[2:0]
Local priority
This bit field is only used when LAPRIOEN bit in CAN_CTL0 register is set.
This bit filed is only used for Tx mailboxes, while these bits are not transmitted, they
are appended to the regular ID to define the transmission priority.
28:18
ID_STD[10:0]
Identifier for standard frame
In standard frame format, only these 11 most significant bits (28 to 18) are used for
frame identification in both reception and transmission cases. The 18 least
significant bits are ignored.
17:0
ID_EXD[17:0]
Identifier for extended frame
In extended frame format, ID_STD[10:0] & these bits are used for frame
identification in both reception and transmission cases.
MDESx: Mailbox descriptor word x (x = 2..17)
Address offset: 0x80 + 0x04 * x (x = 2..17)
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
DATA_i[7:0]
1[7:0]
rw
rw
15
14
13
12
11
rw
9
8
7
6
5
4
3
2
1
0