AeroComm Corporation 44249AJ Manuale Utente

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4.4
4.4
4.4
4.4     AC4424 AT C
AC4424 AT C
AC4424 AT C
AC4424 AT C
OMMANDS
OMMANDS
OMMANDS
OMMANDS
    
The AT Command mode implemented in the AC4424 creates a virtual version of the 
Command/Data pin.  The “Enter AT Command Mode” Command asserts this virtual pin Low 
(to signify Command Mode) and the “Exit AT Command Mode” Command asserts this virtual 
pin High (to signify Data).  Once this pin has been asserted Low, all On-the-Fly CC Commands 
documented in the manual are supported. 
When in AT Command Mode, the user cannot send or receive RF packets.  However, an 
ambiguity of approximately 10ms exists where, if the “Enter AT Command Mode” command 
has been sent to the transceiver at the same time an RF packet is being received, the RF 
packet could be sent to the OEM Host before the “Enter AT Command Mode” command 
response is sent to the OEM Host. 
NOTE: The RF packet size must be set to a minimum of 6 bytes in order to enter Command 
NOTE: The RF packet size must be set to a minimum of 6 bytes in order to enter Command 
NOTE: The RF packet size must be set to a minimum of 6 bytes in order to enter Command 
NOTE: The RF packet size must be set to a minimum of 6 bytes in order to enter Command 
mode us
mode us
mode us
mode using the Enter AT Command mode command.
ing the Enter AT Command mode command.
ing the Enter AT Command mode command.
ing the Enter AT Command mode command.    
4.4.1
4.4.1
4.4.1
4.4.1     Enter AT Command Mode
Enter AT Command Mode
Enter AT Command Mode
Enter AT Command Mode    
Prior to sending the “Enter AT Command Mode” command to the transceiver, the OEM Host 
must ensure that the RF transmit buffer of the transceiver is empty (if the buffer is not 
empty, the ”Enter AT Command Mode” command will be interpreted as packet data and will 
be transmitted out over the RF).  This can be accomplished by waiting up to one second 
between the last transmit packet and the AT Command.  The OEM Host must also ensure 
The OEM Host must also ensure 
The OEM Host must also ensure 
The OEM Host must also ensure 
that the RF Packe
that the RF Packe
that the RF Packe
that the RF Packet Size for the transceiver is set to a minimum of six.
t Size for the transceiver is set to a minimum of six.
t Size for the transceiver is set to a minimum of six.
t Size for the transceiver is set to a minimum of six.  The Enter AT 
Command mode command is as follows: 
OEM Host Command:
OEM Host Command:
OEM Host Command:
OEM Host Command:    
 
41h 54h 2Bh 2Bh 2Bh 0Dh 
 
Transceiver Response:
Transceiver Response:
Transceiver Response:
Transceiver Response:    
   
CCh 43h 4Fh 4Dh 
4.4.2
4.4.2
4.4.2
4.4.2     Exit AT Command Mode
Exit AT Command Mode
Exit AT Command Mode
Exit AT Command Mode    
To exit AT Command Mode, the OEM Host should send the following command to the 
transceiver: 
OEM Host Command:
OEM Host Command:
OEM Host Command:
OEM Host Command:    
 
CCh 41h 54h 4Fh 0Dh