opengt
 set com 115200n81
 set comecho off
 set senddelay 0.02
 waitquiet 0.2 0.2
 flash 0.1

:start
 send "AT+CUSD=1,"
 send $env("ussd")
 send ",15"
 send "^m"
 waitfor 120 "+CUSD:"
 if % = -1 goto timeout
 get 1 "^m" $s
 print $s
 exit 0

:timeout
 print "ERROR: no USSD response, timeout.\n"
 exit 1