UART Registers
19.5.1.31 System Configuration Register (SYSC)
The AUTOIDLE bit controls a power-saving technique to reduce the logic power consumption of the
module interface; that is, when the feature is enabled, the interface clock is gated off until the module
interface is accessed. When the SOFTRESET bit is set high, it causes a full device reset. The system
configuration register (SYSC) is shown in
and described in
Figure 19-64. System Configuration Register (SYSC)
15
5
4
3
2
1
0
Reserved
IDLEMODE
ENAWAKEUP
SOFTRESET
AUTOIDLE
R-0
R/W-0
R/W-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 19-62. System Configuration Register (SYSC) Field Descriptions
Bit
Field
Value
Description
15-5
Reserved
0
Reserved.
4-3
IDLEMODE
0-3h
Power management req/ack control.
0
Force idle: Idle request is acknowledged unconditionally.
1h
No-idle: Idle request is never acknowledged.
2h
Smart idle: Acknowledgement to an idle request is given based in the internal activity of the module.
3h
Smart idle Wakeup: Acknowledgement to an idle request is given based in the internal activity of
the module. The module is allowed to generate wakeup request. Only available on UART0.
2
ENAWAKEUP
Wakeup control.
0
Wakeup is disabled.
1
Wakeup capability is enabled.
1
SOFTRESET
Software reset. Set this bit to 1 to trigger a module reset. This bit is automatically reset by the
hardware. Read returns 0.
0
Normal mode.
1
Module is reset.
0
AUTOIDLE
Internal interface clock-gating strategy.
0
Clock is running.
1
Reserved.
19.5.1.32 System Status Register (SYSS)
The system status register (SYSS) is shown in
and described in
Figure 19-65. System Status Register (SYSS)
15
1
0
Reserved
RESETDONE
R-0
R-0
LEGEND: R/W = Read/Write; R = Read only; -n = value after reset
Table 19-63. System Status Register (SYSS) Field Descriptions
Bit
Field
Value
Description
15-1
Reserved
0
Reserved.
0
RESETDONE
Internal reset monitoring.
0
Internal module reset is ongoing.
1
Reset complete.
3533
SPRUH73H – October 2011 – Revised April 2013
Universal Asynchronous Receiver/Transmitter (UART)
Copyright © 2011–2013, Texas Instruments Incorporated