There are several steps to achieve the configuration you want.
1 With Com Profibus, configure the Profibus Network. Use the 545-1104 from the Master folder for the Master. In the zip file, I have included the GSD files for the 315-2PN/DP and the 315-2PN/DP V3. You will have to install the one you need in the GSD directory of Com Profibus. You should also add the bitmap to the BITMAP directory.
2. Configure the I/O for the 315. Right mouse click on the 315 and select Configure. You will be adding I/O. You can configure up to 244 bytes of Input and 244 bytes of Outputs.
3. Export the configuration to a binary file, File > Export. Don't forget to save your configuration.
4. Using TISOFT or SoftShop merge the binary file into the I/O configuration
5. In the 545 program, you will write to the ouput area and read from the input area created by the merge to read data from and write date to the 315.
6. In the 315 program, the data ouput from the 545 will be read in to the program from the input area you defined. The data you write to the output area will appear as Inputs to the 545
7. Data of lengths greater than a byte must be byte swapped since one controller is Big Endian and the other is Little Endian.
The zip file includes a Com Profibus configuration with the 315 -2PN/DP firmware version prior to V3.
Consulting Sales Application Engineer
Siemens Industry, Inc.
Industrial Automation Systems
1900 Musket Court
Stone Mountain, GA 30087