Industry News, Trends and Technology, and Standards Updates

EDA/Interface A versus SECS/GEM SEMI Standards

With the growing interest in the use of SEMI EDA/Interface A standards, we have been getting a great deal of requests for the difference between Interface A and SECS/GEM

For a quick comparison, here is a table to showing some of the differences between Interface A and SECS/GEM:

EDA/Interface A versus SECS/GEM 

EDA/Interface A






Can be configured for SSL-secured communications

HSMS is not secure

Equipment Model

You can upload a description of the logical structure of the equipment which includes parameters, events, and exceptions assigned to modules, subsystems, and I/O devices

Equipment information is found in a manual provided with the equipment, but often without the necessary context


Start & stop triggers that may include one or more events and/or exceptions  Traces begin via a SECS message and end when a specified number of samples are collected

Event Reports

Specify an event and an optional set of parameters to be collected when that event occurs

GEM host defines collections of parameters called reports, then links one or more reports to one or more events. The same report may be linked to multiple events if needed.

Data Collection Reports

E134 allows data collection to be throttled if data collection is reducing equipment performance below a specified level

GEM does not throttle back data collection


Additional Resources:

Topics: Industry Standards, SECS/GEM, EDA/Interface A

Posted by Cimetrix on Oct 13, 2014 4:11:00 PM