This section introduces the functional core of a channel, consisting of the following blocks:
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up/down counting,
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enable.
The following illustration shows the up/down counting functional core of the TSX CTY2A or 4A modules.
NOTE: this illustration is very similar to that of the counting only or down counting only function. The main differences are at the level of the physical inputs. The associated language objects are described in the
implicit objects part.
The hardware or software counter enable function is a particular function, intrinsically associated to the up/down counting main function. Indeed, without the counter enable, the counting or down counting functions cannot operate. For this reason, unlike the other functions, the counter enable function is present in this case.
The up/down counting function accepts four counting physical input configurations, which are described in the table below.
This table summarizes the input characteristics of the up/down counting function (for each channel).
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Modules involved
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TSX CTY 2A / 4A
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Input configuration
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One physical input IA ST_IA (%IWr.m.c.2.0) and one software input (counting direction).
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Two physical inputs: IA (main) and IB ST_IB (%IWr.m.c.2.1) (counting direction).
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Two physical inputs: IA (counting) and IB (down counting).
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Three physical inputs: IA and IB on the incremental encoder and IZ ST_IZ (%IWr.m.c.2.6) on the encoder turn pulse.
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Enable
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