--- title: Cimetrix SECS/GEM Terminology description: Cimetrix SECS/GEM Terminology including gem equipment, hsms, gem compliance, secs ii, pv2, --- [![Cimetrix-PDF-combined-logo](https://www.cimetrix.com/hs-fs/hubfs/logos/Cimetrix-PDF-combined-logo.png?width=361&height=100&name=Cimetrix-PDF-combined-logo.png "Cimetrix-PDF-combined-logo")](https://www.cimetrix.com?hsLang=en) [English](https://www.cimetrix.com/?hsLang=en) - [한국어](https://www.cimetrix.com/kr?hsLang=en) - [日本語](https://www.cimetrix.com/jp?hsLang=en) - [中文简体](https://www.cimetrix.com/cn?hsLang=en) - [中文繁體](https://www.cimetrix.com/tw?hsLang=en) - [ Products ** ](https://www.cimetrix.com/secs-gem-terminology#) #### [Smart Connected Equipment](https://www.cimetrix.com/equipment?hsLang=en) - ##### Connectivity - [CIM300](https://www.cimetrix.com/cim300?hsLang=en) - [CIMConnect](https://www.cimetrix.com/cimconnect?hsLang=en) - [CIMPortal Plus](https://www.cimetrix.com/cimportal?hsLang=en) - ##### Control - [CIMControlFramework](https://www.cimetrix.com/cimcontrolframework?hsLang=en) - #### [Smart Connected Factory](https://www.cimetrix.com/factory?hsLang=en) - [Sapience](https://www.cimetrix.com/sapience?hsLang=en) - #### [Utilities](https://www.cimetrix.com/utilities?hsLang=en) - [ECCEPlus](https://www.cimetrix.com/ecce?hsLang=en) - [EquipmentTest](https://www.cimetrix.com/equipmenttest?hsLang=en) - [EDATester](https://www.cimetrix.com/edatester?hsLang=en) ##### Schedule a Demo Today! 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GEM allows the host to be notified when alarm conditions are detected and cleared. | | Collection Event | A collection event is a "detectable occurrence significant to the equipment" that "is considered to be significant to the host". [SEMI E30, 2] GEM allows the host to be notified when a collection event occurs. This allows the host to track the equipment's activity. | | Data Variable | Data variables "…may only be valid upon the occurrence of a particular event". [SEMI E5, 6.6]. The host can gather data variable values from the GEM Equipment. The data variable values provide information specifically related to the event. | | Equipment Constant | Equipment Constants are "settable by the Host"[SEMI E5 6.6]. The host can gather equipment constant values from the GEM Equipment. The host can also set equipment constant values on the GEM Equipment to control the equipment's behavior. | | GEM Equipment | An "intelligent system which communicates with a host" [SEMI E4, 2.1] and complies to the SECS/GEM standard. | | Host | "An intelligent system which communicates with the equipment." [SEMI E4, 2.1]. The host can be viewed as a line management system. GEM does not intend to define how the host should behave. The GEM SECS standard defines the set of messages a host must use when interacting with GEM Equipment. A GEM Equipment can communicate with one host. A host can communicate with multiple GEM Equipment. | | HSMS-SS | [SEMI standard High Speed Message Service-Single Session](https://www.cimetrix.com/hsms?hsLang=en) which defines TCP/IP network communication used by SECS/GEM for host/equipment communication. It is replacing the SECS-I standard. Only one client host can use a specific port at a time. | | [PV2](https://www.cimetrix.com/pv2?hsLang=en) | GUIDE FOR PV EQUIPMENT COMMUNICATION INTERFACES (PVECI), based on SECS/GEM, specifically for photovoltaic equipment suppliers. | | Process Program | A Recipe (see Recipe) | | Recipe | A set of instructions for the equipment. | | Report | "A set of variables predefined by the equipment or defined by the host…". The host uses reports to gather status variable, data variable, and equipment constant values. The host can request a report explicitly or attach a set of reports to a collection event. | | Status Variable | "Status variables may include any parameters that can be sampled in time such as temperature or quantity of a consumable." [SEMI E5, 6.5] "Status values … always contain valid information." [SEMI E5, 6.6]. The host can gather status variable values from the GEM Equipment. | | SECS-I | SEMI Equipment Communications Standard 1 Message Transfer - defines RS-232 serial communication used by SECS GEM for host/equipment communication. It is phasing out due to inherent speed limitations. It is being replaced by the HSMS standard. | | SECS-II | [SEMI Equipment Communications Standard 2 Message Content](https://www.cimetrix.com/secs-ii?hsLang=en). SECS GEM is a specific implementation of the SECS-II standard. SECS-II defines most concepts and functionality used in the SECS/GEM standard. Many SECS-II capable systems are not GEM compliant. | | SECS-II Message | All GEM Equipment and host communication is accomplished using SECS-II messages. Each unique SECS-II message is identified by its stream number (S) and function number (F). The SECS-II standard defines a large set of SECS-II messages determining each one's purpose, content, and usage. The SECS GEM standard defines how to use a subset of these SECS-II messages yet allows other SECS-II messages to be used in addition to this subset. To learn more about SECS Messaging, download the [primer](https://www.cimetrix.com/secs-messaging-primer/?hsLang=en). |   ![secs/gem semiconductor wafer](https://www.cimetrix.com/hs-fs/hubfs/Cimetrix%20Feb2017%20Theme/Images/shutterstock_55287853%20(round).png?width=225&name=shutterstock_55287853%20(round).png "secs/gem semiconductor wafer") Find out more by selecting from the material available or schedule a meeting with a Cimetrix representative. 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