Commodore Amiga A500 Technical Reference Manual page 9

EXTERNAL SYSTEM v0 This section describes each I10 interface in detail, and some of the
tradeoffs made with respect to AI 000 compatibility.
The Amiga 2000 and Amiga 500 have differences in the serial and
parallel ports from the Amiga 1000, the main difference being
changes in the sex of each port (changing the serial to female and the
parallel to male), which allows the new Amigas to use standard inter-
face cables.
RS232
and MIDI Port
The RS232 connector on the A500 and A2000 is form fit and func-
tion identical to a Commodore PC- 10120 with a few exceptions. This
is the OPPOSITE sex
connector from
the A1 000.
The connector
is a shielded male DB25P connector. The A1 000 supplies various
non-standard RS232 signals on the DB25 connector. These non-
standard signals were removed wherever possible. The RS232 con-
nectar is NOT physically compatible with some MIDI interfaces but is
compatible with the ~ m i g a ~ o d e m / 1 2 0 0 RS (model 1680). Below is
a comparison chart between the RS232 standard, a Hayes Smart-
modem standard, the A1 000 RS232, and the new Amiga 50012000
RS232 connector.
AS001
PIN RS232
A1000 A2000 PC10 HAYES@ DESCRIPTION
GND
T x D
R x D
RTS
CTS
DSR
GND
DCD
-
-
S.SD
S.CTS
S.T
X
D
T x C
S.R
X
D
R x C
-
S.RTS
DTR
SQD
R I
SS
T x C l
-
Frame ground
Transmit Data
Receive Data
Request to send
Clear to send
Data set ready
Signal ground
Carrier detect
+
1 2 volt power
- 1 2 volt power
Audio output
Speed Indicate
GND
T x D
R x D
RTS
CTS
DS R
GND
DCD
GND
T x D
R x D
RTS
CTS
DSR
GND
DCD
+
12v
-
12v
AUDO
-
CND
T x D
R x D
RTS
CTS
DSR
CND
DCD
+
12v
-
12v
GND
T x D
R x D
-
CTS
DSR
GND
DCD
-
-
5Vdc
AUDO
AUDl
EB
INTZ*
-
5 volt power
Audio output
Audio input
Port clock 71
6KHz
Interrupt IineJAudio input
AUDl
DTR
+
5Vdc
DTR DTR
-
DTR
Data terminal ready
+
5 volt power
Ring indicator
+
1 2 volt power
3.58MHz
clock
Buffered system reset
C2*
RESB*