LM3S2730 Luminary Micro, Inc, LM3S2730 Datasheet - Page 348

• Manufacturer Part Number: LM3S2730
• Description: Lm3s2730 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Reset
Reset
Type
Type
Controller Area Network (CAN) Module
CAN Transmission Request 1 (CANTXRQ1)
CAN0 base: 0x4004.0000
Offset 0x100
Type RO, reset 0x0000.0000
348
Bit/Field
31:16
15:0
RO
RO
31
15
0
0
Register 30: CAN Transmission Request 1 (CANTXRQ1), offset 0x100
Register 31: CAN Transmission Request 2 (CANTXRQ2), offset 0x104
The CANTXRQ1 and CANTXRQ2 registers hold the TxRqst bits of the 32 message objects. By
reading out these bits, the CPU can check which message object has a transmission request pending.
The TxRqst bit of a specific message object can be changed by three sources: (1) the CPU via the
CAN IFn Message Control (CANIFnMCTL) register, (2) the message handler state machine after
the reception of a remote frame, or (3) the message handler state machine after a successful
transmission.
The CANTXRQ1 register contains the TxRqst bit of the first 16 message objects in the message
RAM; the CANTXRQ2 register contains the TxRqst bit of the second 16 message objects.
RO
RO
30
14
0
0
reserved
RO
RO
29
13
TxRqst
0
0
Name
RO
RO
28
12
0
0
RO
RO
27
11
0
0
Type
RO
RO
RO
RO
26
10
0
0
0x0000
Reset
0x00
RO
RO
25
0
9
0
Preliminary
RO
RO
24
0
8
0
Description
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Transmission Request Bits
(of all message objects)
0: The message object is not waiting for transmission.
1: The transmission of the message object is requested and is not yet
done.
reserved
TxRqst
RO
RO
23
0
7
0
RO
RO
22
0
6
0
RO
RO
21
0
5
0
RO
RO
20
0
4
0
RO
RO
19
0
3
0
RO
RO
18
0
2
0
July 25, 2008
RO
RO
17
0
1
0
RO
RO
16
0
0
0