其中一段,谁能给我解释一下啊????

Reading Consistent Data of a DP Standard Slave//PROFINET IO Device with SFC 14 "DPRD_DAT"
Description

With SFC 14 "DPRD_DAT" (read consistent data of a DP standard slave), you read the consistent data of a DP standard slave/PROFINET IO device.

To find the maximum length that applies for S7-300 CPUs, refer to the manuals, Automation System S7-300, Hardware and Installation, ET?00S Interface Submodule, IM151-7 CPU, or Base Submodule BM147CPU. For S7-400 CPUs refer to the manual Automation System S7-400 CPU Data. If no error occurred during the data transfer, the data that have been read are entered in the destination area identified by RECORD.

The destination area must have the same length as configured for the selected module with STEP 7.

If you read from a DP standard slave with a modular design or with several DP identifiers, you can only access the data of one module/DP identifier per SFC 14 call specifying the configured start address.

Writing Consistent Data to a DP Standard Slave/PROFINET IO Device with SFC 15 "DPWR_DAT"
Description

With SFC 15 "DPWR_DAT" (write consistent data to a DP standard slave), you transfer the data in RECORD consistently to the addressed DP standard slave/PROFINET IO device and, if required, to the process image (namely if you have configured the respective address area of the DP standard slave as consistency range in a process image). To find the maximum length of the data to be transferred for S7-300 CPUs, refer to the manuals, Automation System S7-300, Hardware and Installation, ET?00S Interface Submodule, IM151-7 CPU, or Base Submodule BM147CPU. For S7-400 CPUs refer to the manual Automation System S7-400 CPU Data. The data is transferred synchronously, in other words, on completion of the SFC, the write job is also completed.

The source area must have the same length as you configured for the selected module with STEP 7.

If the DP standard slave has a modular design, you can only access one module of the DP slave.

看样子你的程序是上传得来的？或者是供货商根本就不想让你看源程序？