Yesterday I wrote a short tutorial for NodeMCU board, and one visitor mentioned WiFiMCU board that has a similar form factor as NodeMCU, and while it is more expensive at about $10 on Aliexpress or Ebay, it is also more powerful and provides more I/Os thanks to its EMW3165 module including an STM32 Cortex M4 micro-controller with 128KB RAM, 512KB flash, a Broadcom WiFi module, and 2MB SPI flash.
- MCU – STMicro STM32F411CE Cortex-M4 microcontroller @ 100MHz with 128KB RAM, 512KB flash
- Storage – 2MB SPI flash
- WiFi – Broadcom 802.11 b/g/n RF Chip:
- 2x 15-pin headers with
- 17x GPIO Pin
- 3x UARTs
- 5x ADC, 1x SPI, 1x I2C, 1x USB
- SWD debug interface
- 11x PWM
- Misc – Boot and Reset buttons
- Power Supply – 5V via micro USB port
- Dimensions –
- Certifications – CE, FCC
- Temperature Range – -30℃ ~ +85℃ (operating)
- The firmware includes a Lua Interpreter just like NodeMCU firmware, and you can connect to the terminal via the micro USB port @ 115200 8N1. The company, DoIT.am (Doctors of Intelligence and Technology), also provides WiFiMCU Studio debugging and firmware upgrade tool available for Windows only.
Source code, schematics (PDF), and documentation for WiFiMCU are available on Github, and look pretty decent. For example you can check out WiFiMCU tutorial (PDF) in perfectly understandable English. Around 48KB memory is available once the firmware is installed, so you’ll have a bit more memory to play with some features like https, which seems hard (but possible) to implement on ESP8266.
Thanks to Andrew for the tip.