FreeWave Technologies Inc. AMI0032AT Manuale Utente

 Spread Spectrum Wireless Data Transceiver User Manual 

Preliminary GXM Manual 

Version 0.2 

22 

These settings are not utilized in the GXM. 

This menu specifies the hardware flow control for the Data port. The options for 0-3 
are described below. 

   0                        None               Default - Uses software control (XON XOFF) 
   1 

RTS 

Uses Standard RTS/CTS control lines 

   2 

 DTR 

 

   3 

                DOT   

 

 

The Modbus RTU setting causes the radio to wait for an amount of time, “gathering” data before sending 
that data out the radio link. 

With a Modbus RTU setting of 0 (Disabled), the radio will send data out its radio link as soon as the data 
is received into the serial port. 

With a Modbus RTU setting of 1, the radio will wait for a number of slots equal to 2 times the Master 
Packet Repeat setting before sending the received data out the radio link. For example, if Master Packet 
Repeat = 3

, the radio will wait for 6 slots, gathering data up the whole time. At the end of the 6 slots, the 

radio will send all received data in one “burst”. This is the appropriate setting for most Modbus RTU 
devices. 

With a setting of 2 and higher, the radio will wait for a number of slots calculated by the following formula: 

(Modbus RTU Setting + Master Packet Repeat Setting + 1) x 2 

For example, in a radio where the Modbus RTU setting = 2 and the Master Packet Repeat setting = 3, the 
radio will wait for (2+3+1) x 2, or 12 slots.