> This topic is a few weeks old already but for your information, sometimes 'All is well that ends well':
> Our connection handling problem is solved after some help of the Siemens support. Interfacing with the SLS S7 driver to a Siemens PLC directly connecting to a CPU315-2 PN/DP works fine now.
> The problem we had was a timing issue. Most likely the PLC tried to initialize functions to quickly after booting. That made the TCON function got locked sometimes.
>> -----Ursprüngliche Nachricht-----
>> Von: email@example.com
] Im Auftrag von Rod Nussbaumer
>> Gesendet: Mittwoch, 22. Februar 2012 18:20
>> An: Konrad Gajewski
>> Cc: firstname.lastname@example.org
>> Betreff: Re: Connection to Siemens S7 PLC
>> At TRIUMF, we are using our own driver to talk to 400-series Siemens
>> PLCs. It uses asyn, and was modeled after Mark Rivers' modbus PLC
>> driver. The underlying communications protocol is the Siemens
>> FETCH/WRITE protocol over TCP/IP.
>> Rod Nussbaumer
>> ISAC Controls, TRIUMF
>> Vancouver, Canada
>> Konrad Gajewski wrote:
>>> Hello everybody,
>>> I'm new to EPICS and I am planning to control Siemens Simatic S7-200
>>> PLC. I have looked in EPIC documentation and found at least two ways
>>> connect the PLC:
>>> 1. via MODBUS (Asyn) driver over the serial connection (using Siemens
>>> MODBUS RTU library)
>>> 2. using S7plc driver via TCP/IP and a CP 243-1 Ethernet module.
>>> The programming of the PLC is done using Step-7 Micro/WIN V4.0.
>>> Unfortunately I can't open the example STEP 7 PLC project (for S7plc
>>> driver) in Step-7 Micro/WIN.
>>> Do you have any experience with such a configuration or maybe with
>>> S7-1200? Are there any better options?