HART 6 Features Summary HART 6 is a major enhancement to the HART Protocol. Many new features are incorporated to support HCF member and industry user needs for communication with new and more capable smart instrumentation products. The guiding principle for developing all enhancements has been to be backward compatible with HART 5. As a result: HART 6 Master works with HART 5 Slave HART 5 Master works with HART 6 Slave HART 6 device features are available only if both Master and Slave are HART 6 capable HART 6 provides new capabilities and reasons for master applications to communicate with HART devices beyond just device setup and configuration. All HART-capable field devices generate digital process variables and other information of importance to process operation 24 hours a day, 7 days a week, 365 days per year. THIS DATA HAS VALUE, but in the past has mostly gone unused. HART 6 provides additional value as it promotes cyclic access to the secondary variables and diagnostics in HART devices. If you already have previous versions of the HART Specifications, you may notice that the HART 6 specifications look considerably different. Major improvements have been made in consistency and organization. Two additional specifications have been added: Device Family and Block Data Transfer. All documents are now formatted similar to IEC requirements with common sections. Many clarifications are incorporated, common terms defined, and neutral terms used throughout. For example, "transmitter" has been replaced with "device", "sensor" replaced by "transducer", "analog output" changed to "analog channel" and "analog output" replaced by "loop current". You will also find that the number of pages have increased substantially. Many HART 6 enhancements are optional, but some are required. Following is a summary listing the major enhancements indicating "required" or "optional". Device Variable Classification - Required Provides master applications with a simple mechanism to determine the number and type of process related variables (pressure, temperature, etc.) that are available within a device. A key enabler for many HART 6 improvements, this mechanism provides master applications with considerable information about device capabilities. (Commands 0, 8) Extended Device Status - Required One additional byte of well defined status information with Command 0 and new cyclic data access Command 9. This new Extended Device Status byte is in addition to the current device status byte returned with each command response. Provides additional device status alerts such as "Device Needs Maintenance" plus more. (Commands 0, 9) Device Variable Status - Required One byte of well defined status for each Device Variable returned by new cyclic data access Command 9. Enables field devices to self-validate and report on the quality of the data in the command response (good, poor, bad, fixed) plus more. (Command 9) Long Tag - Required This new Long Tag with international (ISO Latin 1) characters allows consistent implementation of the longer tag names required by many industry users. The specifications currently reflect the length of this tag to be 32 characters as outlined in the Long Tag proposal approved by HCF members in January 1998. However, the recent discovery that some existing I/O systems will not "pass-through" the 32 character tag, may cause the number of characters to be reduced in the final specification. The need for this new Long Tag is unquestioned. Only the number of characters is being reconsidered. (Commands 20, 21, 22) Configuration Change Counter – Required Improved mechanism for master applications to determine that a field device configuration has been changed. Protects integrity of plant configuration databases. (Command 0) Device Families – Optional Establishes standard commands and status indicators for devices based on the type of process connection. Standard commands allow sim