Siemens Simatic S7-300 Technical Data Manual page 141

Block diagram of integrated digital I/O of CPUs 313C/313C-2/314C-2
CPU 31xC and CPU 31x, Technical data
Manual, Edition 08/2004, A5E00105475-05
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1L+
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1M
Technical data of CPU 31xC
6.6 Technical data of the integrated I/O
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2L+
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2M
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3L+
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3M
6-31