plcpeople / nodeS7

Node.JS library for communication to Siemens S7 PLCs
MIT License
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Support more than 8192 byte data size #115

Open lpc921 opened 3 years ago

lpc921 commented 3 years ago

Hi, thanks for the great library. I found an issue while trying to read large amounts of data from the PLC. Data after ~8192 has quality "BAD undefined".

After some digging I found the buffer size is set to 8 kB: https://github.com/plcpeople/nodeS7/blob/44a1b5ea697d140340d6bcdf28d92048d3f558eb/nodeS7.js#L2745-L2752 https://github.com/plcpeople/nodeS7/blob/44a1b5ea697d140340d6bcdf28d92048d3f558eb/nodeS7.js#L1044

Is there any reason to limit the size of buffers to 8 kB? I think most S7 PLCs support 64 kB DBs.