AXIOMTEK AX10445 Series, Руководство пользователя

Страница: 24 / 58

AX10445 Module Series User
’
s Manual
Technical Reference
16
7
bit 7
of
data
bit 0
of
data
0 1 2 3 4 5 6
Base Address 0 :
(COM1 - 3F8
COM2 - 2F8)
Receiver Buffer/Transmit Holding Register
7
Receive
Data
Available
0 1 2 3 4 5 6
Base A1 :
0 0 0 0
Modem
Status
Receive
Line
Status
Transmit
Holding
Reg.
Empty
Interrupt Enable Register
7
0 means
Interrupt
pending
0 1 2 3 4 5 6
Base A2 :
0 0 0 0 0
3-bit Interrupt ID
Interrupt Identification Register
7
Wordlength
10-7
11-8
0 1 2 3 4 5 6
Base A3 :
Devisor
Latch
Access
Bit
BREAK
Number
of
Stop Bits
0-1, 1-2
Parity
000=None, 001=Odd,
011=Even
Line Control Register
7
DTR
0 1 2 3 4 5 6
Base A4 :
0 0 0
Loopback
Test
OUT2 OUT1 RTS
Must be 1 for interrupt I/O on PC
Modem Control Register
7
Receive
Data
Ready
0 1 2 3 4 5 6
Base A5 :
0
Overrun
Error
Parity
Error
Framing
Error
BREAK
detected
Transmit
Holding
Reg.
Empty
Trans.
Empty
Line Status Register
7
Delta
CTS
0 1 2 3 4 5 6
Base A6 :
RLSD RI DSR CTS
Delta
RLSD
Delta
RI
Delta
DSR
Modem Status Register
Figure 4 Registers in the 8250 UART