Omega Engineering EN-EIC-325-PCI manual Encoder Interface

1.GENERAL DESCRIPTION

•The EN-EIC-325-PCI handles four axes of user's encoders. Each user's encoder is directly attached to the Encoder Interface on the card.

•The EN-EIC-325-PCI includes eleven logical inputs, and three general

outputs.

•The EN-EIC-325-PCI is I/O mapped.

1.1.ENCODER INTERFACE

Note: Each of the registers IPC, XPC and SPR, mentioned below, represents an unsigned integer 24 bit number ranging from 0 to 16777215. In case the user needs also negative values, he should refer to 16777215 as –1 and so on, thus changing the range 0 – 16777215 to –8388608 – +8388607

Each Encoder Interface includes the following elements:

1.1.1.IPC

The IPC (Internal Position Counter) is updated continuously according to the input from user's encoders.

The updating of the IPC is affected by the Clock Resolution, that may be set to 1, 2 or 4 Clocks/Cycle.

1.1.2.SOFTWARE OUTPUTS

a.The XPC (eXternal Position Counter) is a latch counter being equalized to the IPC upon user's request – either via PC’s software, or by a hardware (real-time) input.

b."Event Signal" – produced when a pre-defined condition is met.

This software Event Signal is supplied also in the hardware outputs as described in section 1.2.2 / ii. The user may select one of the following as the pre-defined condition that becomes the trigger of the event:

•IPC = SPR

Each Encoder Interface includes an SPR (Set Point Register) being adjustable by the user.

In case the user selects this condition, an event occurs when IPC = SPR.

•IPC Overflow

In case the user selects this condition, an event occurs when there's overflow in the IPC, that is, IPC changes from 16777215 to 0, or vice versa.

•Index

In case the user selects this condition, an event occurs when an index (marker) signal arrives from user's encoder.

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