wayne roberts / SX127x

Driver library for SX1272/SX1276 transceivers

Dependents:   LORA_RX LORA_TX WindConcentrator hid_test ... more

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Driver library for SX1272 and SX1276 radio transceivers.

This device uses CSS modulation to provide much improved link budget. The RF hardware is same as in FSK devices, just with added LoRa spread-spectrum modem.

This library provides functions to configure radio chip and transmit & receive packets.

Using This Library

Library function service_radio() must be called continuously from main loop, to service interrupts from radio.

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Board Specific implementation

FunctionPointer for rf_switch callback allows the program to implement control of RF switch unique to their board. Example options are:

  • SKY13373 for external power amplifier implementation. Requires two DigitalOut pins.
  • SKY13350 using PA_BOOST. requires two DigitalOut pins.
  • PE4259-63: controlled directly by radio chip, no software function needed. However, in the case of SX1276MB1xAS, the RXTX pin on IO2 should be driven by this callback function when R16 is installed (without R15) on this shield board.

Some configurations may need to force the use of RFO or PA_BOOST, or a board could offer both options. The rf_switch function pointer callback should support the implementation choice on the board.

further reading

Diff: sx127x_lora.h

Revision:
26:4876e515ff4c
Parent:
23:1df3dddcb43e
Child:
27:da6341d9d5b1
--- a/sx127x_lora.h	Thu Oct 22 01:27:18 2015 +0000
+++ b/sx127x_lora.h	Mon Jul 18 21:13:50 2016 +0000
@@ -154,8 +154,8 @@
 
 typedef union {
     struct {    // sx1276 register 0x36
-        uint8_t freq_to_time_drift_auto         : 1;    // 0  manual control of 0x3a register
-        uint8_t sd_max_freq_deviation_auto      : 1;    // 1  manual control of 0x3b[3:1]
+        uint8_t freq_to_time_drift_auto         : 1;    // 0  manual control of 0x3a register (1=auto)
+        uint8_t sd_max_freq_deviation_auto      : 1;    // 1  manual control of 0x3b[3:1] (1=auto)
         uint8_t reserved                        : 6;    // 
     } bits;
     uint8_t octet;