Visitor notify system Wireless network XBeeS2C + RX621: API Frame2

This is a system that detects people and cars entering the premises of the house through the gate and notifies the people in the house.
The place where the people of the house are is either the purlin, the greenhouse, or the workshop. Because they are far apart, they are connected wirelessly.

When it detects the movement of a person or car and determines that it is necessary to ring the chime, it notifies the other units.
Also, when talking in the sensor range, it tries to avoid the chime ringing many times.
API frame 2 is used for XBee communication, the MPU is Renesas RX621, and the language is C / C ++.

It will be helpful for those who are considering a similar system.
Of course, you can use it with other MPUs by replacing the part that operates the MPU registers.

–––––––-
[Visitor notify system] table of contents

[Introduction]
[Visitor notification system]
1. [Hardware]
(1) Sensor part
(2) Main Box
(3) Chime Box
2. [Wireless module settings]
(1) Main Box
(2) Sensor Box
(3) Chime Box 1
(4) Chime Box 2
3. [Example of API2 frame]
(1) Inquirie
(2) Response
(3) Battery voltage
(4) Chime instruction
(5) Response
4. [Software development]
(1) Software policy
(2) Flowchart
(3) Outline program
5. [Inquiry timing]
(1) Exclusion
(2) Notification
6. [Chime instruction timing]
(1) Main Box
(2) Chime Box
7. [LCD display screen]
8. [Serial Communication]
(1) Inquiry issuing
(2) Chime ON / OFF instruction
(3) Data reception
(3) Response analysis
9. [Measurement of battery voltage]
[All programs]
[Afterword]