SX1278 and ESP32 based POCSAG gateway

• uses Semtech SX1278 as FSK receiver
• also works with Semtech SX1276
• uses W5500 Ethernet transceiver
• receives 1200 bps, 4500 Hz shift POCSAG messages
• serial console logging of received messages
• serial console Command Line Interface for configuration and debugging
• telnet server Command Line Interface for configuration and debugging
• 3 levels of debugging
• write/read configuration to/from flash
• german BOS mode and DAU filter
• german ASCII codes
• decoding of ROT1 encoded messages
• Ethernet based http gateway to forwarding the messages
• error correction by BCH decoding

• GPIO 12 - MISO
• GPIO 13 - MOSI
• GPIO 14 - SCLK
• GPIO 15 - CS

• GPIO 25 - RESET
• GPIO 26 - DIO0
• GPIO 27 - DIO1
• GPIO 32 - DIO2
• GPIO 33 - DIO3 (for future development)

• GPIO 23 - MOSI
• GPIO 19 - MISO
• GPIO 18 - CLK
• GPIO 5 - CS

• center frequency in MHz and Rx error offset frequency in kHz
  • the Rx error offset is the measured AFC value when Rx error offset is set to 0
• bitrate in kbps (e.g. 1.2 for 1200 bps)
• frequency shift in kHz
  • this means the single sided shift (e.g. 4.5 for +/- 4500 Hz)
• Rx bandwidth in kHz (choose the next larger value from table in SX1278.h)
  • this means the single sided bandwidth
  • calculation: RXbandwidth >= Fshift+(bitrate/2)
  • the auto function uses the above formula
• AFC bandwidth in kHz (choose the next larger value from table in SX1278.h)
  • calculation: AFCbandwidth >= 2*(Fshift+(bitrate/2))+Ferror
  • Ferror means the maximum center frequency offset error of the SX1278 module
  • the auto function uses the above formula