Thank you for posting your inquiry here. Can you help clarify what IES you are referring here? Are you referring to Intel Ethernet Switch? Please provide more information.
Yes, the Intel ® Ethernet Switch Family Software API User Guide.
A new product of my company is based on Intel FM10840 switch controller.
I can't find the API guide.
Further checking, you need an NDA to obtain the said information. Please visit below website to register to request for NDA:
Please feel free to update me if further assistance needed.