How do I send data from my gateway to node

End Devices (Nodes)
4

The LMiC documentation explains:

struct lmic_t {
 u1_t frame[MAX_LEN_FRAME];
 u1_t dataLen; // 0 no data or zero length data, >0 byte count of data
 u1_t dataBeg; // 0 or start of data (dataBeg-1 is port)
 ...

…

For the EV_RXCOMPLETE and EV_TXCOMPLETE events, the txrxFlags field sould be evaluated and the following flags are defined:

  • …
  • TXRX_PORT: a port field is contained in the received frame
  • …

And to print the downlink data to the serial output, see Downlink to Node with LMIC - #9 by arjanvanb.