User Manual
Table Of Contents
- Overview
- Control Protocols
- WiFi
- Configuration
- USB Configuration Commands
- ST Status. Return the system status
- RB ReBoot.
- IP Sets the modules IP address.
- SB Sets the SuBnet mask.
- GW Sets the GateWay address.
- PD Sets the Primary DNS.
- SD Sets the Secondary DNS.
- SS This sets the SSID.
- PW Sets your networks WIFI password.
- PA Sets the TCP/IP port number for the ASCII commands.
- MS Sets the MQTT broker address
- MD Sets the MQTT ID for this module
- MP Sets the MQTT broker’s port.
- R1-R8 Sets the MQTT topic this relay is subscribed to.
- N1-N8 Sets the MQTT topic this Input will publish to.
- TCP/IP Commands.
- HTML Commands.
- Webpage
- Schematics
- PCB dimensions
- Notes
ESP32SR88 User Manual v1.00
Overview
The ESP32SR88 is a WIFI connected relay module using the popular ESP32.
It provides eight optically isolated inputs and eight volt free contact relay outputs with a current rating
of up to 1Amp each.
Power for the board is 12v dc, which can be provided by a standard universal wall power supply. A 1A
or greater supply should be selected.
Control Protocols
1. Simple plain text commands sent to the module.
2. HTML commands
3. MQTT
4. A built in webpage
WiFi
The ESP32SR88 connects via 2.4GHz WiFi to your network, therefore it must be located in a position
where it gets a good WiFi signal. The module should not be enclosed in a metal box/cabinet as this will
shield the WiFi signal.
You can check the signal level by looking at the RSSI figure which is reported by the ST (STatus)
command.
Configuration
The ESP32SR88 is configured by connecting a USB cable to your PC and running a terminal program,
PuTTY is a good option if you don’t have any other preferences.
The serial port should be set to 115200 baud, 8 bit, 1 stop, no parity, no flow control.
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