Bluepill + W5500 Ethernet MQTT Client using PlatformIO
This project uses a "W5500 lite" board (also called DEVMO USR-ES1) connected to a standard BluePill board (STM32F103C8).
WIZnet - W5500
x 1
This project uses a "W5500 lite" board (also called DEVMO USR-ES1) connected to a standard BluePill board (STM32F103C8).
The code is a slight extension of the original ArduinoEthernetShield.ino (https://github.com/256dpi/arduino-mqtt/blob/master/examples/ArduinoEthernetShield/ArduinoEthernetShield.ino) sketch with the addition of reading out the supply voltage of the board.
No changes to the Ethernet or arduino-mqtt library have been made.
Refer module datasheet for details.
- Power pins: All GNDs to Bluepill's GNDs, all VIN3.3 pins to Bluepill's 3.3V
- since the module is power-hungry, extra decoupling capacitors on the 3.3V rail are recommended
- SPI: use default SPI1 (SCK = PA5, MISO = PA6, MOSI = PA7) and arbitrary chip select (here CS = PA4)
- nRESET of W5500 module must be tied to 3.3V, otherwise the chip won't start
- INT and POWERDOWN are not used
The Serial UART output is on PA9 at 115200 baud.
The sketch should start with detecting the W5500 chip and getting an IP address via DHCP. It then connects to a public MQTT broker, subscribes to the "/hello" topic and regularly publishes a dummy message in the topic.
W5500 detected
Local IP is 192.168.1.237
connecting...
connected!
Incoming: from topic "/hello" Payload "01234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Publishing message to /hello: "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
Incoming: from topic "/hello" Payload "world"
- Datasheet W5500 Module: https://www.usriot.com/download/ES1/USR-ES1-EN-V1.0.pdf
- Datasheet W5500 chip: http://wizwiki.net/wiki/lib/exe/fetch.php/products:w5500:w5500_ds_v109e.pdf
- STM32Duino Bluepill pinout: https://stm32duinoforum.com/forum/wiki_subdomain/index_title_Blue_Pill.html