HEIDENHAIN TNC 426 B User Manual page 349

Non-HEIDENHAIN devices
The connector pin layout of a non-HEIDENHAIN device may differ
considerably from that on a HEIDENHAIN device.
This often depends on the unit and type of data transfer. The figure
below shows the connector pin layout on the adapter block.
RS-422 Adapter X21
block TNC
334
13 Tables and Overviews
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