ISD94100 Series Technical Reference Manual
Sep 9, 2019
Page
608
of 928
Rev1.09
IS
D
9
410
0
S
ER
IE
S
T
E
C
HN
ICA
L
RE
F
E
RE
NCE
M
AN
U
AL
UART Alternate Control/Status Register (UART_ALTCTL)
Register
Offset
R/W Description
Reset Value
UART_ALTCTL
U0x2C
R/W UART Alternate Control/Status Register
0x0000_000C
31
30
29
28
27
26
25
24
ADDRMV
23
22
21
20
19
18
17
16
Reserved
ABRDBITS
ABRDEN
ABRIF
Reserved
15
14
13
12
11
10
9
8
ADDRDEN
Reserved
RS485AUD
RS485AAD
RS485NMM
7
6
5
4
3
2
1
0
Reserved
Bits
Description
[31:24]
ADDRMV
Address Match Value
This field contains the RS-485 address match values.
Note:
This field is used for RS-485 auto address detection mode.
[23:21]
Reserved
Reserved. Any values read should be ignored. When writing to this field always write with
reset value.
[20:19]
ABRDBITS
Auto-baud Rate Detect Bit Length
00 = 1-bit time from Start bit to the 1st rising edge. The input pattern shall be 0x01.
01 = 2-bit time from Start bit to the 1st rising edge. The input pattern shall be 0x02.
10 = 4-bit time from Start bit to the 1st rising edge. The input pattern shall be 0x08.
11 = 8-bit time from Start bit to the 1st rising edge. The input pattern shall be 0x80.
Note :
The calculation of bit number includes the START bit.
[18]
ABRDEN
Auto-baud Rate Detect Enable Bit
0 = Auto-baud rate detect function Disabled.
1 = Auto-baud rate detect function Enabled.
Note :
This bit is cleared automatically after auto-baud detection is finished.
[17]
ABRIF
Auto-baud Rate Interrupt Flag (Read Only)
This bit is set when auto-baud rate detection function finished or the auto-baud rate counter
was overflow and if ABRIEN(UART_INTEN [18]) is set then the auto-baud rate interrupt will
be generated.
0 = No auto-baud rate interrupt flag is generated.
1 = Auto-baud rate interrupt flag is generated.
Note:
This bit is read only, but it can be cleared by writing “1” to ABRDTOIF
(UART_FIFOSTS[2]) and ABRDIF(UART_FIFOSTS[1]).
[16]
Reserved
Reserved. Any values read should be ignored. When writing to this field always write with
reset value.
[15]
ADDRDEN
RS-485 Address Detection Enable Bit
This bit is used to enable RS-485 Address Detection mode.