DCAN Registers
23.4.1 CTL Register (offset = 00h) [reset = 1401h]
CTL is shown in
and described in
.
The Bus-Off recovery sequence (refer to CAN specification) cannot be shortened by setting or resetting
Init bit. If the module goes Bus-Off, it will automatically set the Init bit and stop all bus activities. When the
Init bit is cleared by the application again, the module will then wait for 129 occurrences of Bus Idle (129 *
11 consecutive recessive bits) before resuming normal operation. At the end of the bus-off recovery
sequence, the error counters will be reset. After the Init bit is reset, each time when a sequence of 11
recessive bits is monitored, a Bit0 error code is written to the error and status register, enabling the CPU
to check whether the CAN bus is stuck at dominant or continuously disturbed, and to monitor the
proceeding of the bus-off recovery sequence.
Figure 23-19. CTL Register
31
30
29
28
27
26
25
24
Reserved
WUBA
PDR
R-0h
R/W-0h
R/W-0h
23
22
21
20
19
18
17
16
Reserved
DE3
DE2
DE1
IE1
InitDbg
R-0h
R/W-0h
R/W-0h
R/W-0h
R/W-0h
R-0h
15
14
13
12
11
10
9
8
SWR
Reserved
PMD
ABO
IDS
R/WP-0h
R-0h
R/W-5h
R/W-0h
R/W-0h
7
6
5
4
3
2
1
0
Test
CCE
DAR
Reserved
EIE
SIE
IE0
Init
R/W-0h
R/W-0h
R/W-0h
R-0h
R/W-0h
R/W-0h
R/W-0h
R/W-1h
LEGEND: R/W = Read/Write; R = Read only; W1toCl = Write 1 to clear bit; -n = value after reset
Table 23-14. CTL Register Field Descriptions
Bit
Field
Type
Reset
Description
31-26
Reserved
R
0h
25
WUBA
R/W
0h
Automatic wake up on bus activity when in local power-down mode.
Note: The CAN message, which initiates the bus activity, cannot be
received.
This means that the first message received in power down and
automatic wake-up mode, will be lost.
0x0 = No detection of a dominant CAN bus level while in local
power-down mode.
0x1 = Detection of a dominant CAN bus level while in local power-
down mode is enabled. On occurrence of a dominant CAN bus level,
the wake up sequence is started.
24
PDR
R/W
0h
Request for local low power-down mode
0x0 = No application request for local low power-down mode. If the
application has cleared this bit while DCAN in local power-down
mode, also the Init bit has to be cleared.
0x1 = Local power-down mode has been requested by application.
The DCAN will acknowledge the local power-down mode by setting
bit PDA in the error and status register. The local clocks will be
turned off by DCAN internal logic.
23-21
Reserved
R
0h
20
DE3
R/W
0h
Enable DMA request line for IF3.
Note: A pending DMA request for IF3 remains active until first
access to one of the IF3 registers.
0x0 = Disabled
0x1 = Enabled
3924
Controller Area Network (CAN)
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated