Owners manual

Interfaces
H3 Datasheet(Revision1.2) Copyright© 2015 Allwinner Technology Co.,Ltd.All Rights Reserved. Page 477
This is used to indicate that the modem control line dcd_n has changed
since the last time the MSR was read.
0: no change on dcd_n since last read of MSR
1: change on dcd_n since last read of MSR
Reading the MSR clears the DDCD bit.
Note: Ff the DDCD bit is not set and the dcd_n signal is asserted (low) and a
reset occurs (software or otherwise), then the DDCD bit is set when the
reset is removed if the dcd_n signal remains asserted.
2
R
0
TERI
Trailing Edge Ring Indicator
This is used to indicate that a change on the input ri_n (from an active-low
to an inactive-high state) has occurred since the last time the MSR was read.
0: no change on ri_n since last read of MSR
1: change on ri_n since last read of MSR
Reading the MSR clears the TERI bit.
1
R
0
DDSR
Delta Data Set Ready
This is used to indicate that the modem control line dsr_n has changed since
the last time the MSR was read.
0: no change on dsr_n since last read of MSR
1: change on dsr_n since last read of MSR
Reading the MSR clears the DDSR bit. In Loopback Mode (MCR[4] = 1), DDSR
reflects changes on MCR[0] (DTR).
Note: If the DDSR bit is not set and the dsr_n signal is asserted (low) and a
reset occurs (software or otherwise), then the DDSR bit is set when the
reset is removed if the dsr_n signal remains asserted.
0
R
0
DCTS
Delta Clear to Send
This is used to indicate that the modem control line cts_n has changed since
the last time the MSR was read.
0: no change on ctsdsr_n since last read of MSR
1: change on ctsdsr_n since last read of MSR
Reading the MSR clears the DCTS bit. In Loopback Mode (MCR[4] = 1), DCTS
reflects changes on MCR[1] (RTS).
Note: If the DCTS bit is not set and the cts_n signal is asserted (low) and a
reset occurs (software or otherwise), then the DCTS bit is set when the reset
isremoved if the cts_n signal remains asserted.
8.3.5.12. UART Scratch Register(Default Value: 0x00000000)
Offset: 0x001C
Register Name: UART_SCH
Bit
R/W
Default/Hex
Description
31:8
/
/
/
7:0
R/W
0
SCRATCH_REG
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