Hello Guys The SECS-II(SEMI Equipment Communication Standard 2), which is also recognized as SEMI E5, is used by the semiconductor industry as a protocol for communication between devices involved in manufacturing. SECS-II is a layer above HSMS & SECS-I. SECS-I and HSMS outline how the communication takes place (such as over RS-232C or Ethernet), SECS-II defines the format and content of messages that can be sent over SECS-I/HSMS. The SECS II explains the message structure between equipment and host. SEMI E5 standard is a large library of messages – a few of which have redundant functions with different message structures. Most equipment supports a limited subset of these messages. Some equipment defines custom SECS-II messages that are not part of the SEMI E5 standard. GEM standard requires only a few subsets of messages. Few SECS-II message transactions can be initiated by the Host and few can be initiated by equipment. And few may be initiated either by host or equipment.SECS 2 messages should have the correct party and correct message format as defined by E5.