4.2 FAX and Data Function
Only EasyGate GSM with fax converter supports fax and data functions. Fax converter is available for GSM versions of EasyGate only.
Sending fax message or modem connection to and from GSM
GSM fax and Data connection
EasyGate with fax converter has ability to send and receive GSM fax messages using analogue fax Group 3 connected to telephone line FXS. The fax communication service must be registered with your GSM operator. It is possible to establish data connection using analog modem connected to FXS line. It is useful for devices with build-in modem, without possibility to use serial line. The data communication service must also be registered with your GSM operator.
Sending a fax message to GSM and modem connection through GSM (UMTS, LTE)
When connected device is able to send CNG tone (1100 Hz for fax 1300 Hz for modem), the gateway recognizes whether the call is fax or data, the connection will be established automatically. When the tone is not send or some problems with recognition occurred, is necessary to dial before destination number code *01* for fax call or *02* for data call. This code us used to inform the Gateway, that the call is a fax or data call.
Receiving a fax message from GSM
It is recommended to activate separate fax number on your SIM card – multinumbering scheme. Fax messages must be routed to fax number, data call to data number. Incoming fax, data and voice calls will be than automatically recognized. It is possible to set ring pattern for fax and data call, different from the pattern for voice call.
If the fax or data number is not activated, the call from analogue network routed to your GSM number is not detected as fax or data call and is routed via the analogue channel of GSM network and the connection is not successful. In this case it is possible to set the gateway using DTMF commands using device connected to FXS line. These commands can be used for data and fax routing to FXS line or serial line.
DTMF codes for fax receive:
- *9900# Reset of all following settings for fax receive
- *9901# The next call is fax, this setting is suspended after receiving call or by command *9900#
- *9902# Fax routed to FXS, inactivate *9900# or device reset +
- *9903# Fax routed to COM, inactivate *9900# or device reset +
DTMF codes for data receive:
- *9800# Reset of all following settings for data receive
- *9801# The next call are data, this setting is suspended after receiving call or by command *9800#
- *9802# Data routed to FXS, inactivate *9800# or device reset +
- *9803# Data routed to COM, inactivate *9800# or device reset +
Commands marked + are used to set parameters, which can be set permanently in configuration program (PCManager). Using DTMF commands has higher priority, than setting in configuration program, but is valid only till reset of gateway or inactivating command.
Setting for the next call is only alternative solution, which is not able to substitute using of multinumberig scheme (e.g. when unexpected voice call is incoming before the fax or data call, this solution disables to receive it).
Supported fax and data protocols
Supported fax protocols
The gateway supports connection of analogue Fax Group 3 using protocols V.29, V.27 and V.27ter. Maximal data rate is 9,6 kbps. The maximal data rate is strongly dependent on line quality, which is tested on the beginning of connection, to avoid data errors. The fax service is available up to field strength -90 dBm.
Supported data protocols
The gateway supports connection of analogue modem using protocols V.90, V.34, V.32bis, V.32, V.22bis, V.22, V21, Bell 212A and Bell 103. Maximal data rate is 56kbps. For connection between two modems is the data rate limited by the CSD data rate in GSM network, the maximum is 14,4 kbps.
Higher data speed could be useful only for GPRS connection. The maximal data rate is strongly dependent on line quality, which is tested on the beginning of connection, to avoid data errors. The data rate for GPRS connection is limited by actual speed of GPRS transfer in GSM network too. This speed is often affected by network load.
Connection using IP stack
Function IP stack is available on special versions of EasyGate only. It is dedicated for connection of device with embedded analogue modem to defined server on internet public address. The connection must be initialized by connected device with embedded analogue modem by special dialing prefix *02*. EasyGate will establish data channel to preset server by TCP connection.