C M L - 5 4 8 5 U S E R M A N U A L V 1 . 0
0 6 / 2 2 / 0 5
9
COM1 and COM2 Ports
The COM1 and 2 ports provide standard 9 pin serial connection with RS232 type interface to
the MCF5485 UART0 and UART1 peripherals respectfully. The COM1 port is applied by the
dBUG monitor at 19.2K baud default. Both ports will connect to a standard PC COM port with
a straight through type 9 pin serial cable. Following is the DB9S connection reference.
COM1 or COM2
1
1
X
TXD
2
6
6
RXD
3
7
7 CTS
4
4
8
8 RTS
GND
5
9
9
The
COM-1or 2
port is a DB9 socket connector with RS232
signal levels.
RXD
maybe isolated from port by option, see chart below.
CTS / RTS
are enabled by options, see chart below.
1,4,6 connected for status null to host
The 1, 4, 6 and 9 pins provide RS232 status signals. These DB9 connector locations are
provided access pads behind the connector.
COM PORT OPTIONS
The following table provides COM options and default connections to the MCF5485
Programmable Serial Controllers (PSC).
Port
Signal
Option
Default
MCF5485 Signal
COM1
RXD
RXD0
Closed
PSC0RXD
COM1
RTS
RTS0
Open
PSC0RTS
COM1
CTS
CTS0
Open
PSC0CTS
COM2
RXD
RXD1
Closed
PSC1RXD
COM2
RTS
RTS1
Open
PSC1RTS
COM2
CTS
CTS1
Open
PSC1CTS
Notes:
1) All options are SMT 0805 component size pads.
2) Default closed options must be opened by cutting trace between option pads.
3) To close an option a SMT 0805 resistor of 0 ohms maybe applied.