Digi NS9215 Benutzerhandbuch
. . . . .
S E R I A L C O N T R O L M O D U L E : H D L C
Wrapper Configuration register
www.digiembedded.com
423
Register
Register bit
assignment
assignment
13
12
11
10
9
8
7
6
5
4
3
2
1
0
15
14
31
29
28
27
26
25
24
23
22
21
20
19
18
17
16
30
Reserved
Reserved
Reserved
LL
RL
CRC
RX
CLOSE
RXBYTES
Reserv
ed
RXEN TXEN MODE
RX
FLUSH
TX
FLUSH
Bits
Access
Mnemonic
Reset
Description
D31
N/A
Reserved
N/A
N/A
D30
R/W
RXEN
0
0
Disable wrapper function
1
Enable wrapper to process receive characters
D29
R/W
TXEN
0
0
Disable wrapper transmitter function
1
Enable wrapper to process transmit characters
D28
R/W
MODE
0
Applies only to UART channel C.
0
0
UART mode
1
HDLC mode
D27:18
N/A
Reserved
N/A
N/A
D17
R/W
RXFLUSH
0
Resets the contents of the 64-byte RXFIFO.
Write a 1, then a 0 to reset the FIFO.
Write a 1, then a 0 to reset the FIFO.
D16
R/W
TXFLUSH
0
Resets the contents of the 64-byte TX FIFO.
Write a 1, then a 0 to reset the FIFO.
Write a 1, then a 0 to reset the FIFO.
D15:14
R
RXBYTES
00
Indicates how many bytes are pending in the wrapper.
The wrapper writes to the RX FIFO only when 4 bytes are
received or a buffer close event occurs, such as end of
frame.
The wrapper writes to the RX FIFO only when 4 bytes are
received or a buffer close event occurs, such as end of
frame.
D13
R/W
RXCLOSE
0
Allows software to close a receive buffer. Hardware
clears this bit when the buffer has been closed.
0
clears this bit when the buffer has been closed.
0
Idle or buffer already closed
1
Software initiated buffer close
D12
R/W
CRC
0
Controls whether the HDLC transmitter hardware sends
CRC bytes before the closing flag.
0
CRC bytes before the closing flag.
0
Send CRC bytes before the closing flag
1
Do not send CRC bytes before the closing flag;
handled by software
handled by software
D11:06
N/A
Reserved
0
N/A
D05
R/W
RL
0
Remote loopback
Provides an internal remote loopback feature. When the
RL field is set to 1, the receive HDLC data signal is
connected to the transmit HDLC data signal.
Provides an internal remote loopback feature. When the
RL field is set to 1, the receive HDLC data signal is
connected to the transmit HDLC data signal.