DCAN Control Registers
1114
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Controller Area Network (DCAN) Module
23.17.30 CAN TX IO Control Register (DCAN TIOC)
The CAN_TX pin of the DCAN module can be used as general-purpose IO pin if CAN function is not
needed.
NOTE:
The values of the IO Control registers are only writable if Init bit of CAN Control Register is
set.
The OD, Func, Dir, and Out bits of the CAN TX IO Control register are forced to certain
values when Init bit of CAN Control Register is reset (see bit descriptions).
Figure 23-74. CAN TX IO Control Register (DCAN TIOC) [offset = 1E0h]
31
19
18
17
16
Reserved
PU
PD
OD
R-0
R/W-D
R/W-D
R/WP-0
15
4
3
2
1
0
Reserved
Func
Dir
Out
In
R-0
R/WP-0 R/WP-0 R/WP-0
R-U
LEGEND: R/W = Read/Write; R = Read only; WP = Protected Write (protected by Init bit); D = Device-dependent; -
n
= value after reset;
U = Undefined
Table 23-30. CAN TX IO Control Register Field Descriptions
Bit
Field
Value
Description
31-19
Reserved
0
These bits are always read as 0. Writes have no effect.
18
PU
CAN_TX Pullup/Pulldown select. This bit is only active when CAN_TX is configured to be an input.
0
CAN_TX Pulldown is selected, when pull logic is active (PD = 0).
1
CAN_TX Pullup is selected, when pull logic is active (PD = 0).
17
PD
CAN_TX pull disable. This bit is only active when CAN_TX is configured to be an input.
0
CAN_TX pull is active.
1
CAN_TX pull is disabled.
16
OD
CAN_TX open drain enable. This bit is only active when CAN_TX is configured to be in GIO mode
(TIOC.Func = 0).
0
The CAN_TX pin is configured in push/pull mode.
1
The CAN_TX pin is configured in open drain mode.
Forced to 0 if Init bit of CAN control register is reset.
15-4
Reserved
0
These bits are always read as 0. Writes have no effect.
3
Func
CAN_TX function. This bit changes the function of the CAN_TX pin.
0
CAN_TX pin is in GIO mode.
1
CAN_TX pin is in functional mode (as an output to transmit CAN data).
Forced to 1 if Init bit of CAN control register is reset.
2
Dir
CAN_TX data direction. This bit controls the direction of the CAN_TX pin when it is configured to be
in GIO mode only (TIOC.Func = 0).
0
The CAN_TX pin is an input.
1
The CAN_TX pin is an output.
Forced to 1 if Init bit of CAN control register is reset.
1
Out
CAN_TX data out write. This bit is only active when CAN_TX pin is configured to be in GIO mode
(TIOC.Func = 0) and configured to be an output pin (TIOC.Dir = 1). The value of this bit indicates
the value to be output to the CAN_TX pin.
0
The CAN_TX pin is driven to logic low (0).
1
The CAN_TX pin is at logic high (1).
Forced to Tx output of the CAN Core, if Init bit of CAN Control register is reset.