Access control system 3

When using it, you need to connect the D3 pin to the 5V external power supply with a 10K resistor to determine whether the external power supply is connected. Compensate and calculate the difference in battery power through the internal program. The system is already in the dormitory, and the field test time is as long as 3 months, stable operation: It has two power supply modes: external power supply and internal power supply, realizing automatic switching of dual power supplies, but there are still some small bugs. It will be solved in subsequent new versions, and there is no big problem now. It is powered by an internal battery, so there is no problem at all. You don’t need to pull the wire privately when using it in the dormitory, and you will not be punished. It has an automatic shutdown 1 minute after triggering and a delay circuit. The trigger is solved by a pure circuit.
 
Attachment: Source program
video:
 
Subsequent version upgrades are still being planned. Thanks to Jialichuang for providing free PCB proofing services, as well as the support of device rolls and PCB proofing coupons a long time ago. Thanks to Jialichuang for providing such a development environment, which makes development simple and allows you to realize some of your own design ideas. Don’t be deterred by the expense of proofing. Thank you to Jialichuang for your company along the way.