RF star networking

I have a project I’m in the initial stages of putting together. The project will
be based on the Explore 100 microcontroller by Geoff Graham, see Silicon Chip
Magazine September 2016. Programmed in Geoff’s MMBasic Ver 5.2. This project
will have four sensor stations and a control station which I would like to link
together using a bidirectional RF star network, over a distance of less than
100m. The Explore 100 supports TTL RS232, SPI, I2C, and 1-wire serial as well as
parallel communications. I would prefer a high level interface. Any suggestions
would be appreciated. Thanks

It might be easiest to use the MikroElektronika Click boards for WiFi.

Otherwise I’d suggest ESP8266 modules, using TTL (3.3V) RS232. These can be used as is, or programmed with NodeMCU or Forth. The ESP-01 module is simplest; it needs 3.3V supply and the serial pins. The centre of the star would be configured as an access point, and the outer rim nodes configured as stations. You’re up for fabricating some mechanical support for the module. Also some programming of each module.