Configuring the Modem
wire, half-duplex mode (SW3-7 ON), the modem squelches the receiver after RTS is turned off to prevent far-end echoes from causing data errors. The duration that the modem squelches the receiver is either:
8 milliseconds if the modem is configured for Bell 202 mode (SW2-1 OFF)
150 milliseconds if the modem is configured for ITU-T V.23 mode (SW2-1 ON)
SW2-3 FSK Soft Carrier (Bell 202 FSK Mode Only)
SW2-3 ON = None
OFF = 8ms
SW2-3 controls the soft carrier and is valid for Bell 202 FSK mode only (SW2-1 set to OFF). Setting this switch to OFF configures the modem to transmit a 900 Hz soft carrier to the remote modem for 8 milliseconds after RTS is turned off. Setting this switch to ON prevents the modem from transmitting a soft carrier after RTS is turned off.
SW2-4 and SW2-5 RTS-CTS Delay (Bell 202 Mode Only)
Switches SW2-4 and SW2-5 determine the duration of the RTS-CTS delay in Bell 202 mode. Table 2-4 shows how to set these switches to select the appropriate setting.
Table 2-4. RTS-CTS Delay Settings in Bell 202 Mode
| | |
To Select | Set SW2-4 to… | And Set SW2-5 to… |
a Delay of… | | |
8ms | OFF | OFF |
| | |
33ms | OFF | ON |
| | |
59ms | ON | OFF |
| | |
219ms | ON | ON |
| | |
