The company I work for has an embedded product that runs on linux.

We have a big customer that wants the data from our product to be integrated into their VTScada system. Our data consist of simple booleans, integers, floats, and strings.

As you might guess our management has asked me to investigate the effort it would take to implement.

Where can I start? Can someone point me to a document? Is there an API I can review.

Depending on the simplicity and power of your product, you should probably consider installing one of these three on your device to serve the data to VTScada and many other systems.

1. For simple devices - Install a Modbus stack (Floats take Two Registers).

2. For more complex devices - Install an OPC-UA server.

3. Best for simpler systems (Currently) - Install an MQTT Publisher. Note this will require a broker to be set up as well. See Mosquitto

I'll probably do ModBus then. When you say ModBus I assume that ModBus TCP will work?

You got it. Modbus TCP is built into VTScada.

You can learn how to make that work in VTScada or Free VTScadaLight by watching this quick start video: https://youtu.be/dvBmQwLnDvA