3Com manual PathBuilder S330/S310 Serial Port LEDs

50CHAPTER 2: INSTALLATION

Table 18 Connector Pinouts for X.21 DCE cable (60-pin Connector) to DB-15 Female

	Pin # on 60-pin	Pin # on DB-25	Direction (for
Signal Name	Connector	Connector	Serial Port)
Frame GND	46	1
Circuit GND	15	8
RTS	1, 2	3, 10	In
CTS	9, 10	5, 12	Out
DSR			Out
DCD (DCD should be			Out
tristated when in DTE
mode)
DTR			In
LL (not used)			In
SD+	28	2	In
SD-	27	9	In
RD+	11	4	Out
RD-	12	11	Out
SCTE+			In
SCTE-			In
SCR+ (SCR+ and -	24	6	Out
should be tristated
when in DTE mode,
double term., double
buffer)
SCR-	23	13	Out
SCT+			Out
SCT-			Out
Shorting GR 1	47, 48

Serial Port LEDs In addition to the common LEDs described earlier in this chapter, the following LEDs indicate the status of the serial port. See Figure 20.

RD active (green)—Flashes with receiving signals.

TD active (green)—Flashes with transmitting signals.

Figure 20 PathBuilder S330/S310 Serial Port LEDs

TD RD