User manual
Appendix A Hayes Commands
Man_805U Rev 1.9 Page 55
&T1 Receive Bit Error Rate Test. Receives data from &T0 module, and records BER
statistics.
&T2 Transmit & Receive BER Test. Used with a second module configured as a
transparent repeater.
&T3 RSSI Measurement. Monitors the received signal strength, and displays in dBm.
AT&V View Current Configuration – List the value of all settings as well as S-Registers.
&V0 Same as AT&V
&V1 Only show settings that are different from the defaults.
AT&U Set module’s Unit Address Range 0-127. Default 1.
AT&W Write Current Configuration to non-volatile storage
AT&Z Stored Numbers – Up to 4 destination addresses may be stored.
Format: “AT&Zx=nn,nn,nn,nn”. “x” = 0 to 7. “nn” = 1 to 127.
AT&Z0 is used for auto-connect address.
AT\T Inactivity Timeout – Units Seconds. Value 0-255. Default = 0 (disable). If there is
no radio activity in controlled mode within this time, the module resets the
connection. If used, should be larger than the value in S6.
S-Registers
S-Registers provide a method of storing operational parameters of the module. A radio
module has different requirements to a telephone module, so functions of the S-Registers are
also different. S-Registers may be examined using the command ATSn?, where n is the
number of the S-Register. S-Registers may be modified using the command ATSn=xx, where
n is the S-Register number, and xx is the new value for the register.
S-Registers and functions are listed below:
No. Range Function Comment
S0 0-255 Number of attempts before
answering connection
message
Should normally be set to 1 - 0 disables auto
answering of calls (ATA only).
S1 3-255 Escape Sequence Guard
Time (units 20 milliseconds)
default = 50
Units 20 milliseconds. Min. Delay before
and after entering the escape sequence
(“+++”) also Max. Delay between characters
of the escape sequence.
S2 1-255 Escape Sequence Character Normally 43 = “+” (ASCII code)
S3 0-127 Carriage Return Character Normally 13 = <CR>
S4 0-127 Line Feed Character Normally 10 = <LF>
S5 0-127 Back Space Character Normally 8 = <BS>
S6 0-255 Link Check Timer Units Seconds. 0 disables. How frequently
to send a “Link Check” message. Usually