Burkert Type 8605 - Manual (Page 11)

11
Serial Communication
Telegram 3.4.
general information 3.4.1.
The layout of the transmission telegram is based on the HART protocol. HART is a master slave protocol, i.e.
each transmission is started by a master device (PC or manual operating unit). The slave device (field device, 8605)
responds only to a master telegram if the device was addressed by the telegram.
Exception: Burst message
Additional information about the HART protocol may be found under:
http://www.hartcomm.org/
A distinction is drawn between short frame and long frame telegrams. They consist of the following characters:
Short frame
Preamble 2 ... 20 Bytes 0xFF
hex
(differs from HART: 5...20 bytes)
delimiter 1 byte
Master → Slave 0x02
hex
Slave → Master 0x06
hex
Burst message 0x01
hex
Address 1 byte (Master address + Burst info + Polling address)
Command 1 byte
Byte count 1 byte
Status 2 bytes, only for slave → master
data 0 ... 255 (... 255 (-2)) bytes
Checksum 1 byte
long frame
Preamble 2 ... 20 bytes 0xFF
hex
(differs from HART: 5...20 bytes)
delimiter 1 byte
Master → Slave 0x82
hex
Slave → Master 0x86
hex
Burst message 0x81
hex
Address 5 bytes
Command 1 bytes
Byte count 1 byte
Status 2 bytes, only for slave → Master
data 0 ... 255 bytes
Checksum 1 byte
english
Typ 8605