IEC 61158-4-21 : 1.0已作废
INDUSTRIAL COMMUNICATION NETWORKS - FIELDBUS SPECIFICATIONS - PART 4-21: DATA-LINK LAYER PROTOCOL SPECIFICATION - TYPE 21 ELEMENTS
出版：International Electrotechnical Committee
专家解读视频
Describes procedures for giving communication opportunities based on standard ISO/IEC 8802-3 MAC, with provisions for nodes to be added or removed during normal operation.
NF EN 61158-4-21 : 2013 - Identical
NBN EN 61158-4-21 : 2012 - Identical
DS EN 61158-4-21 : 2012 - Identical
BS EN 61158-4-21 : 2012 - Identical
CEI EN 61158-4-21 : 2013 - Identical
NEN EN IEC 61158-4-21 : 2012 - Identical
PN EN 61158-4-21 : 2012 - Identical
DIN EN 61158-4-21 : 2013 - Identical
