EUCHNER CIS3(A) - Manual (Page 6)

EUCHNER Identsystem CIS3
071652-01-8/99 Subject to technical modifications page 6 / 23
4. Basic telegram structure without response telegram
Each command and any related data blocks are transferred within the telegram frame in
accordance with Procedure 3964-R from and to the read/write head (Figure 4).
With Protocol 3964-R, the relevant receiver acknowledges the received telegram by
returning an acknowledgement character (DLE). In the case of negative acknowledgement
(NAK), the entire protocol is repeated. If it is not possible to transfer the protocol error-free
after a total of six attempts, the operation is aborted.
4.1 Basic command structure
Description Byte No. C O N T E N T S
ASCII
Acknowledgement
of the receiver
+ -
Connection set-up 3964-R procedure start
STX
DLE NAK
Telegram data
max. 128 Bytes Number of telegram Bytes 0
(telegram core) Command
identification 1
2 T or R
command
Header address *) 3 01h
User data description 4
5
6
Start address
Start address
Number of data
items
User data 7
to n
Connection
cleardown 3964-R Procedure
end DLE
ETX
BCC
DLE NAK
Figure 4 : Basic command structure
*) For downward compatibility with the CIS2 identification system.
The content of the header address must always be 1 in the case
of CIS3.