# GEX protocol documentation This repository specifies the control protocol implemented by [gex-core](https://github.com/gexpander/gex-core). ## General information - [FRAME_FORMAT.md](FRAME_FORMAT.md) - Low level frame format, message types - [INTERNAL_STRUCTURE.md](INTERNAL_STRUCTURE.md) - GEX's internal structure, units, requests and events - [INI_FILES.md](INI_FILES.md) - INI config files, filesystem and API access ## Unit types - [UNIT_DO.md](UNIT_DO.md) - Digital Output - [UNIT_DI.md](UNIT_DI.md) - Digital Input - [UNIT_NEOPIXEL.md](UNIT_NEOPIXEL.md) - NeoPixel driver - [UNIT_SIPO.md](UNIT_SIPO.md) - Shift Register Driver with multicast support - [UNIT_I2C.md](UNIT_I2C.md) - I2C master - [UNIT_SPI.md](UNIT_SPI.md) - SPI master up to 16 slaves and multicast support