Spectrum Controls SLC 500, Руководство пользователя

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Chapter 5: Programming Examples 5-5
User’s Manual Pub. 0300181-07 Rev. A
external gate enable, and the associated pulses that the module will accumulate:
Given the above wave form, the module will begin counting the first positive
going input pulse after the external enable input goes low. The module will
accumulate 4 counts in the channel count register and stop when the external
enable input goes high.
The external enable line accommodates 5 VDC, 12 VDC and 24 VDC signals
and is pulled low internally. The counter input accommodates 5 VDC, 12 VDC,
24 VDC and up to 75 VAC inputs.
Section 5.7
Application Note:
Factor Data Errors
The 1746sc-CTR4/8 module provides a feature that allows the user to load M, K
and Rate factor values into module memory without consuming additional
control registers. In order to accommodate this feature into the design, three of
the four registers assigned to each channel of the module are multiplexed with
the Counter Preset, Limit and Rate limit values.
If factored data values are inadvertently loaded into the module without user
knowledge of this occurring, the module can appear to be non-functional.
Follow these steps to identify if factored data values have been loaded and if so,
how to clear those values to return the module to default operation.
• Use Channel Status registers to identify the presence of Factored Data
values
•
Use Bits 12 and 13 in the channel status registers to verify if factored
data is present. If either or both of the bits are set to a one the module
has factor data values loaded.
The following table contains the addresses for the channel status registers:
Channel Register
0 I:e.3 (Where e indicates
slot where module is
installed)
1 I:e.7
2 I:e.11
3 I:e.15
CTR8 only:
4 I:e.19