Intel 386

5-15
DEVICE CONFIGURATION
Figure 5-8. Serial I/O Unit 0 Configuration
To DMA
TXEDMA0
To ICU
SIOINT0
A2521-02
BCLKIN
Receive Data
Transmit Data
Request to Send
SIO0
Clear to Send
Data Set Ready
Data Terminal
Ready
Data Carrier
Detect
Ring Indicator
0
1
COMCLK
(P3.7)†
To/From I/O Port 3
P3CFG.7
SERCLK
SIOCFG.0
† Alternate pin signals are in parentheses.
RXD0
(P2.5)
0
1
CTS0#
(P2.7)
SIOCFG.6
To/From I/O Port 2
RTS0#
(P1.1)
P1CFG.1
0
1
0
1
P2CFG.7
DTR0#
(P1.2)
To/From I/O Port 1
P1CFG.2
0
1
V
CC
To/From I/O Port 2
P2CFG.5
TXD0
(P2.6)
To/From I/O Port 2
P2CFG.6
To/From I/O Port 1
DSR0#
(P1.3)
To/From I/O Port 1
P1CFG.3
DCD0#
(P1.0)
To/From I/O Port 1
P1CFG.0
RI0#
(P1.4)
To/From I/O Port 1
P1CFG.4
To DMA
RBFDMA0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0