User's Manual

905U-D Radio Modem Module User Manual
Page 30 © May 2000
Operating mode (S0) ATS0 = xxx Default = 4
xxx Option Connect Mode
0 Transparent mode without error-check Host
1 Transparent mode with error-check Host
2 Controlled mode without error-check Host
3 Controlled mode with error-check Host
4 Transparent mode without error-check Auto
5 Transparent mode with error-check Auto
6 Controlled mode without error-check Auto
7 Controlled mode with error-check Auto
8 Transparent mode repeater Auto
NOTE The operating mode may also be changed using the mode command (AT&Mx)
Operating modes 0 to 3 try to duplicate the operation of conventional telephone modems,
and can be used with software designed to operate with telephone modems. The 905U-D
units will start up in configuration mode, expecting Hayes command configuration. See 3.3
Controlled Mode for a description of operation.
Tail time (S1) ATS1 = xxx Default = 0
where xxx is the tail time in 10 msec increments ( xxx = 20 for 200 msec )
A tail time may be configured which keeps the radio transmitter active at the end of each
message. The maximum tail time is 2.55 seconds. The tail time value is the 8-bit binary
equivalent of the desired time in 10 msec increments.
Escape character (S2) ATS2 = xxx Default = 43 (“+”)
where xxx is the decimal ASCII value of the character. The default value is 43 (“+”).
A host device may force the unit to configuration mode by sending three “escape” characters
- “+++”. The default escape character is “+”, however this may be changed by the host
device.
ATS2 = 255 will prevent the unit entering command mode.
Maximum message length (S3) ATS3 = xxx Default = 265
where the maximum message length in bytes is equal to twice xxx plus 10, or 2 *
(xxx) + 10.
For example, ATS3 = 10 gives a maximum length of 30 bytes.
The message length parameter selects the maximum length (in bytes) of the data sent in
each radio message. The length may be selected between 10 bytes and 520 bytes. The
message length is equal to 2x(VALUE)+10, where VALUE is the decimal equivalent of the 8-
bit code entered.
Serial data rate (S4) ATS4 = xxx Default = 8
To select or change the serial data rate, enter the following VALUE code. The serial data
rate can be different at different 905U-D modules in the same system. The default value is
9600 bits/sec.