Motorola and V.32bis, V.34-SDC manual Models 3261/3263/3266/3268 only. Signal passed from modem to

Table B-1.

Modem/Computer Interface Connections (Continued)

	EIA/TIA
Pin	232-D	ITU V.24		Signal	Definition
12	CI	112		Data Signal Rate	CI (112) is passed from modem to terminal, indicating signaling rate.
				Indicator	When signal is on, modem operates at 2400 bps or greater. When
					signal is off, modem operates below 2400 bps.
13	—	110		Signal Quality	Signal passes from modem to terminal indicating signal quality of
					telephone line. When signal is on, signal quality is acceptable. When
					signal is off, signal quality is poor.
14	—	—	Ext Select		(All models.) Signal passed from terminal to modem to select between
					two option sets. Works in conjunction with Ext Select option.
					(Models 3261/3263/3266/3268 only.) Signal passed from terminal to
					modem indicating whether to use a dial line or a leased line. When
					signal is on, modem uses a dial line. When signal is off, modem uses a
					leased line. This signal is used in Restoral mode only.
15	DB	114		Transmitter	Local modem sends an internally generated transmit timing signal to
				Signal Element	local terminal to synchronize transmitted data (TXD). See
				Timing	Clock=Internal.
16	—	117		Standby Indicator	(Models 3261/3263/3266/3268 only.) Signal passed from modem to
					terminal indicating type of line in use. When signal is on, modem is on
					a dial line. When signal is off, modem is on a leased line. This signal is
					used in Restoral mode only.
17	DD	115		Receive Signal	Timing signal extracted from the received carrier. Local modem
				Element Timing	transmits this signal to the DTE to synchronize received data (RXD).
18	—	141		Local Analog	Initiated at local terminal and passed to local modem, causing it to
				Loopback Test	initiate local analog loopback test.
19	—	—	—	Not used.
20	CD	108.1/		Data Terminal	108.1—Sent by DTE; causes the modem to connect to the phone line.
		108.2		Ready (DTR)
					108.2—Sent by DTE; allows the modem to connect to the phone line.
21	—	140		Remote Digital	Signal initiated at local terminal and passed to local modem, causing it
				Loopback Test	to initiate remote digital loopback test (V.54 Loop 2).
22	CE	125		Ring Indicator	Passed from local modem to local terminal. On during ringing, off
				(RI)	between rings and when no ring received.
23	CH/CI	111/112		Data Signal Rate	CI passed from modem to terminal indicating signaling rate. CI is set
				Select/Indicator	high for data rates greater than 2400 bps; otherwise, it is set low. CI is
					also set low while the modem is disconnected. The function of this pin
					is determined by the setting of rear panel Switch 1. CH (input) signal
					has no effect on modem operation.
24	DA	113		External Signal	Transmit timing signal generated by some synchronous DTEs,
				Element Timing	providing clock to the local modem. See Clock=External setting.
25	—	142		Test Indicate (TI)	Local modem signals to local terminal when local modem is in test.
					The terminal can initiate a Busy Out condition on this circuit. The

status of this signal is determined by the status of rear panel Switch 2 and front panel option DTE Pin 25 configured for Test or Busy.

Pinouts Interface

Cabling and Interface Pinouts B-3