Multitech MultiModem iSMS SF100-G Administrator's Manual page 79

Modem Modem index to send SMS. SF400/800 models only.
Range : 1 to 4 for SF400
1 to 8 for SF800
0 for any modem (Send API job is distributed using all available modems)
If modem is not specified in the request, send API job is distributed using all the available modems.
to The mobile number where the SMS is delivered.
This number is given in double quotes. The maximum size of each recipient's number is 50 bytes.
text The message text to be sent.
Enable Extended ASCII in the MultiModem iSMS to send both ASCII and extended ASCII characters. By
default, Extended ASCII is disabled and the message can have only ASCII characters.
Notes:
characters can be sent.
If Extended ASCII is enabled and spanned SMS value is 1, a maximum of 140 characters can be sent.
If Unicode is enabled and spanned SMS value is 1, a maximum of 70 characters can be sent.
If the spanned SMS value is more than 1, the maximum number of characters allowed for each
encoding scheme is defined as follows (where n represents the span value):
ASCII – n * 154 characters
Extended ASCII – n * 134 characters
Unicode – n * 64 characters
Any characters entered beyond the allowed limit are truncated.
In the HTTP API format example above: user1, puser1, 7657867765 and message are variables / configured parameters.
79
If Extended ASCII and Unicode are disabled and spanned SMS value is 1, a maximum of 160
Appendix A – Application Programming Interface (API)
MultiModem® iSMS System Administrator's Guide