MIL-STD-2217 CHG NOTICE 1

Abstract

The Memory Loader/Verifier (MLV) will provide the means for loading and verifying avionics memories in military aircraft utilizing a multiplex bus interface. <br>New or modified memory data will first be processed by designated facilities for each avionic system. It will then be transmitted to each user and transferred to the MLV Memory Storage Device (MSD) at the Intermediate Maintenance Activity (IMA). The MSD in each MLV will then contain a completely updated record of all memory data to be loaded into the avionic memories. <br>The MLV, using the interfaces defined herein, will be utilized to reprogram all applicable systems aboard an aircraft at the organizational maintenance level (O-Level). It will load the new data into the memories of the appropriate avionics systems and verify that the memories have been correctly loaded where possible. <br>Two types (Type I and Type II) of aircraft interface connections are called out in this document. The two types are defined in order to allow for compliance with contractual requirements and physical constraints that differ between aircraft. The Type I interface is defined to accommodate the physical constraints of existing aircraft and if within contractual constraints may be used for all existing aircraft. The Type II interface shall be used for all new designs and may be used for any existing aircraft. Individual Interface Control Documents (ICD) for each aircraft will define user definable items such as specific bus connections. These ICDs shall not repeat items specified herein. <br>This standard shall be used for the development of MLV interfaces for all avionic equipment to be reprogrammed via MIL-STD-1553 type bus interfaces. Individual Interface Control Documents (ICDs) for each unit, to specify user definable items described herein, will be required to allow Memory Storage Device preparation. These ICDs shall comply with this document and shall not repeat items specified herein. <br>This standard is applicable to all equipment reprogrammable at "O" level via a MIL-STD-1553 multiplex data bus and all new aircraft or aircraft modified to incorporate avionic equipment in conformance to this standard. All new equipment designs designated as Remote Terminals shall utilize the protocol defined in Appendix B of this document. All new equipment designs designated as Bus Controller shall utilize the protocol of Appendix C of this standard until the MLV is allocated the Bus Controller function and then shall utilize the protocol of Appendix B of this document. Equipment previously designed for which reprogramming capability is being added shall utilize the protocol of Appendix B or C of this document. Only equipment that is currently reprogrammable in the fleet via a MIL-STD-1553 multiplex data bus (or modifications to those equipments) shall utilize the protocol of Appendices D, E, F, G or H. All reprogrammable equipment not committed to production prior to the date of this document shall use at least one reprogramming enable discrete.