Serial Interface Pin Definitions - 3Com 005699-00 Manual

Serial Interface Pin Definitions

DB-25 DB-9 Circuit Function
1 — AA Chassis Ground
2 3 BA Transmitted Data
3 2 BB Received Data
4 7 CA Request to Send
5 8 CB Clear to Send
6 6 CC Data Set Ready
7 5 AB Signal Ground
8 1 CF Carrier Detect
12 — SCF Speed Indicate
20 4 CD Data Terminal Ready
22 9 CE Ring Indicate
T R
ECHNICAL EFERENCE
Signal Source
Computer/Modem
Both
Computer
Modem
Computer
Modem
Modem
Both
Modem
Modem
Computer
Modem
8-38