GOSSEN METRAWATT GMBH 8
2 Telegram structure
All telegrams consist of one of 3 sets in both request and reply direction, they differ in their principal structure.
Their use is fixed for each interface function of the R2600/01.
Structure and use of the set types are described as follows.

2.1 Short set

Short sets are used on the request side (from the master)
•for transmission of short instructions to the equipment (e.g. Reset)
•for short requests of important data from the equipment (e.g. event data)
Short sets are used on the reply side (from the R2600/01)
•for acknowledgement of requests that require no reply data.
Principal construction short set
Character No. Contents Meaning Remarks
110h Start character Especially for short set
20 ... FAh, FFh Equipment address Addr and/or 255 (see 2.4.1)
3Function field (FF) see 2.4.2
4Checksum (PS) = Equipment address + FFh
516h End character Common to all set types