Appendix C Hayes AT Command Reference
RFI-9256 Radio Modem User Manual
Page 92 of 109
For the radio to distinguish the escape sequence from ordinary data, there must be a period of silence both
before and after the escape sequence is entered. If the escape sequence guard time is one second and the
escape sequence character has been defined as ‘
+
’, for the radio to recognise an escape sequence the line
must be silent for one second, then “
+++
” is transmitted in rapid succession, and then another one second
silence.
S-register 12 is also used to time the period between the escape sequence characters as they are typed. If the
period between the first and second escape characters or second and third escape characters being entered is
greater than the value in s-register 12, the radio will not recognise the escape sequence.
The guard time is in units of milliseconds (or 1/1000 of a second).
ATS12=990<CR>
: Maintain silence on the line for 990ms (0.99 seconds) before and after entering
the escape sequence.
C.2.5
“ATS21” Set Security Code
S-register 21 sets the network security code for this radio. The range of values is from 0 to 4294967295. All
radios on a single network must have the same security code in order to maintain communications.
ATS21=5839238<CR>
: Sets the security code to 5839238.
C.2.6
“ATS39” RX Packet Timer
S-register 39 contains the RX (in) packetiser timer. Packet timers are in the range 0 to 1000ms. When a
value of 0 is set for s-register 39 packetising is disabled.
ATS39=30<CR>
: Sets a 30ms RX packetisation timer.
ATS39=0<CR>
: Disables the RX packetisation timer.
C.2.7
“ATS40” TX Packet Timer
S-register 40 contains the TX (out) packetiser. Packet timers are in the range 0 to 1000ms. When a value of 0
is set for s-register 40 packetising is disabled.
ATS40=870<CR>
: Sets an 870ms TX packetisation timer.
ATS40=0<CR>
: Disables the TX packetisation timer.
C.2.8
“ATS41” Number of Retries
S-register 41 contains the number of retries used by the radio, and is within the range 0 to 255 where a value
of 0 will disable retries.
ATS41=25<CR>
: Sets 25 retries.
ATS41=0<CR>
: Disables retries.