Simple two-way message appliance

Client message appliance alerts server appliance of message and receives status updates from server

• uses Radiohead http://www.airspayce.com/mikem/arduino/RadioHead/RadioHead-1.100.zip
  • adafruit maintains a GitHub branch at https://github.com/adafruit/RadioHead
• Adafruit NeoPixel https://github.com/adafruit/Adafruit_NeoPixel

• 1X each: Adafruit Arduino Pro Mini 328 - 5V (part 2378) + Adafruit FRM69HCW Radio Breakout (part 3070) + Adafruit FTDI Friend (part 284) or
• 1X: Adafruit Feather M0 RFM69HCW Packet Radio (part 3176)
• 1X: NeoPixel
• 2x: button
• 1 protoboard
• wire

• see Fritzing diagram

• Adafruit RFM69HCW (SPI): https://learn.adafruit.com/adafruit-rfm69hcw-and-rfm96-rfm95-rfm98-lora-packet-padio-breakouts?view=all
• https://learn.adafruit.com/adafruit-feather-m0-radio-with-rfm69-packet-radio
• Radiohead main page: https://www.airspayce.com/mikem/arduino/RadioHead/index.html
• https://community.particle.io/t/my-attempt-at-rf95-lora/40573/3
• https://groups.google.com/forum/#!forum/radiohead-arduino
• https://learn.adafruit.com/adafruit-rfm69hcw-and-rfm96-rfm95-rfm98-lora-packet-padio-breakouts?view=all

• 051120: seems to fall out of sync where X will do something but Y will not be in a state to respond?
• 051920: implement robust error handling; how does the user know what state they are in (visually, programmatically)
• 051920: need to remove delay() loops in code, might be causing sync issues, debug message also gated by delay()

• 041919: do I buffer overrun or truncate when inbound packet is larger than defined buffer len?
• 051920: can I control the timeout on the Reliable Datagram send calls, or do I care as long as the routine is called enough? (aka, unless one of the radios is pooched or out of range, a packet will eventually get to the other node)
• 051920: how to implement a button based reset of the board (for when they fall out of sync)
• 051920: Should we alert or debug log when RSSI is below a described db?

• 051920: Implement app level packet counts, transmitted to both parties, to help implement out-of-sync fixes
• 051920: Create standardized packet, set buffers to that size rather than protocol max (saves memory)
• 051920: Use the builtin LED as a crude indicator (packet send, receive, etc.)

• 050320: first version, adapted from datagram_server
• 050520: [Q 041919] code looks like it could send packets to multiple clients based on form of client_address declare? -> yes
• 050920
  • implemented conditional messaging
  • code is running on Feather M0 RFM69HCW
• 080220
  • conditional visual alert code for NEOPIXEL and RELAY
  • [FR]051920: Capture RSSI in DEBUG for all transmissions