Update NOW.md

This commit is contained in:
HomeSpan 2022-10-09 09:13:07 -05:00 committed by GitHub
parent ac47b35c23
commit 6b9a541bd3
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 5 additions and 2 deletions

View File

@ -1,6 +1,9 @@
# Multi-Device Point-to-Point Communication using ESP-NOW
# SpanPoint: Point-to-Point Communication between ESP32 Devices
Like most commercial HomeKit devices, HomeSpan requires a power-consuming always-on WiFi connection, which unfortunately means powering a HomeKit device with batteries is generally not possible. For most applications, this is not a problem since your HomeSpan device will be controlling a real-world light, fan, thermostat, etc., and will likely be plugged into a wall outlet. However, there are some real-world applications where wall outlets are not readily available and battery-power is essential, such as remote temperature sensors, door and window sensors, or standalone switches.
SpanPoint is HomeSpan's integrated implementation of Espressif's ESP-NOW protocol that enables bi-directional communication from one ESP32 device directly to another without the need for a central WiFi network. In a typical setup, one ESP32 device runs a full HomeSpan sketcs (perhaps for a Thermostat Accessory) and connects to HomeKit in the usual fashion.
ike most commercial HomeKit devices, HomeSpan requires a power-consuming always-on WiFi connection, which unfortunately means powering a HomeKit device with batteries is generally not possible. For most applications, this is not a problem since your HomeSpan device will be controlling a real-world light, fan, thermostat, etc., and will likely be plugged into a wall outlet. However, there are some real-world applications where wall outlets are not readily available and battery-power is essential, such as remote temperature sensors, door and window sensors, or standalone switches.
To address this problem, HomeSpan includes an integrated implementation of Espressif's ESP-NOW protocol that allows for the point-to-point transmission of short messages between ESP32 devices requiring **very little power**. Importantly, ESP-NOW uses the ESP32's existing WiFi radio, so no new hardware is required.