# Protocols

Config-driven protocol clients communicate directly with hardware. Instrument drivers provide
vendor-agnostic abstractions; protocol clients use JSON config files that describe a device
register map or command set.

| Class | Description |
| --- | --- |
| [`ModbusDevice`](https://dev.nominal.io/instro/ref/protocols/modbus.md) | Modbus TCP and RTU devices |
| [`EtherNetIPDevice`](https://dev.nominal.io/instro/ref/protocols/ethernetip.md) | Allen-Bradley PLC tag access |