The type of read / write to preform. Note that not all types can be written. For example an attempt to write to D_INPUTS or INPUTREG would cause an EINVAL error. Also you can not directly write to SETUPREGS, you must use an appropriate Ioctl.
Enumerator |
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COILS | Coils are any relay type outputs.
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D_INPUTS | Digital inputs. Single bit inputs.
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HOLDINGREG | Configuration registers.
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INPUTREG | Registers only used on A/D type devices.
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SETUPREG | Advanced device configuration registers.
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SEAMAXPIO | Programmable type I/O.
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