9
Annex
Page 9-2
gas-net
C1 and C2
This is why in the GW-GNET+ interface the positions for import and export val-
ues are not indicated in the DB/DW form but as serial register numbers.
We therefore recommend to switch to the 3964R protocol type in the program's
surface first, if necessary, and then to position the export data points or import
values during the creation of the parameterisation.
The necessary programming of the host can be minimised by selecting the
Master
operating mode for the gateway side of the RK512 protocol. In this case
it is not necessary to compile a job list for the host as the entire data block
assignment is carried out via the gateway parameterisation. However, at least
the agreed data blocks and the basic protocol functionality must be defined in
the host of course.
The communication between the host and the
gas-net
DSfG gateway is subject
to several basic requirements. The following list provides a summary:
Communication protocol:
RK512/3964R
–
point-to-point
Interface:
V24 with PC/AT pin assignment at the gateway
Transmission rate:
adjustable to 2400, 9600, 19200 or 38400 baud
Transmission parameters:
8 data bits, even parity, 1 stop bit
3964R telegrams:
max. 128 bytes (64 data words) per telegram
RK512 response telegrams:
Max. 64 data words per telegram; no 3964R tele-
gram chains possible. In the RK512 slave operat-
ing mode (i.e. gateway = slave), the gateway
generates the response telegrams listed in the
table below:
