3.2 Connection
External Modem Connection
Modem
To
To CO line/Hybrid
Hybrid
Signal Name | Pin No. |
|
|
|
|
RD (RXD) | 2 |
|
|
|
|
SD (TXD) | 3 |
|
| ||
|
|
|
ER (DTR) | 4 |
|
| ||
|
|
|
DR (DSR) | 6 |
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|
|
|
External Modem
Pin No. | Signal Name |
|
|
3 | RD (RXD) |
|
|
2 | SD (TXD) |
|
|
20 | ER (DTR) |
|
|
6 | DR (DSR) |
|
|
After connecting the Hybrid
The following AT command settings may be required for the modem:
•The Data Terminal Ready (DTR) signal should be ignored.
•The Data Terminal Equipment (DTE)/Modem flow control should be turned off.
•Data compression should be disabled.
•Error Correction is not necessary.
Notes
•Use an
•An AT command (for initialization, enabling automatic answer, etc.) can only be programmed by
•For more information about the AT command, refer to the external modem's instructions.