Rockwell Automation 1794-IF4I, -OF4I, IF2XOF2I, -IF4IXT, -IF4ICFXT, -OF4IXT, IF2XOF2IXT FLEX I/O Isolated Analog Modules - Manual (Page 61)

Publication 1794-6.5.8 - January 2010
Writing Configuration to and Reading Status from Your Module with a Remote I/O Adapter 61
Word 4 Bit 00–03 Channel calibration selection bit. When this bit is set (1), the channel can be calibrated
using the calibration clock bit (CK). Bit 00 corresponds to input channel 0, bit 01 corresponds to
input channel 1, it 02 corresponds to input channel 2, bit 03 corresponds to input channel 3
Bit 04 Gain/Offset selection bit (GO). – When this bit is cleared, a 0 to 1 to 0 transition of the CK
bit performs on offset calibration. When this bit is 1, the module is directed to do a gain
calibration.
Bit 05 Calibration clock bit (CK). – When this bit is set to 1 (calibration mode), the calibration
coeffiicient for the selected channels is accepted. When this bit is reset (0), the accepted
calibration coefficients for the selected channels are stored, applied, and the calibration mode
exited. Monitor status bits DN and BD for succesful calibration.
Bit 06 Quick Calibration bit (QK). – Normally reset (0). When this bit is set (1) during a calibration
sequence, the calibration coefficient is stored to all related configurations for the selected
channels. NOTE: This method of calibration quickly calibrates the selected channels, however
you will not be within the rated accuracy of the module.
Bit 07 Revert to defaults bit (RV). – Normally reset (0). When set (1) during a calibration procedure,
default values for selected channels are used for the calibration coefficient.NOTE: You will not
be within the rated accuracy of the module.
Bits 08-11 (10-13) Not used. Set to 0.
For IF4ICFXT only:
Bit 8 — FastStepResponse (FR) forces the A/D to skip the FIR stage if an input step occurs.
An averaging algorithm is temporarily used instead of the FIR filter in the A/D to provide a
quicker response.
Bit 9 — FIRFilterDisable (SK) bypasses the FIR filter stage in the A/D.
Bit 10 — ChopModeDisable (CH) disables the chop mode in the A/D. Chop mode is used to
reduce offsets between input and output of the analog section of the A/D.
(1)
Note: Module level settings that only affect 150 Hz, 300 Hz, and 600 Hz conversion rate
settings.
Bit 12 (14) Interrupt Toggle bit (IT) – This bit, when set (1), permits interleaving of module interrupts
ensuring exchange of critical data when channels are configured for their fastest update times.
RTSI and “no low pass filter” must be 0 in order for the module to recognize this feature. This
groups data update rates for all channels to the slowest configuration setting of any of the
channels. In addition, channel update rates for all channels with a 7.5ms update rate are
reduced to 5.0ms. When reset (0), real time sampling and filter features are enabled.
Bit 13 (15) Transparent bit (TR). – This bit, when set to 1, permits configuration to be changed without
using the IC bit. Default setting for this bit is True (1)
Bit 14 (16) Always set to 1.
Bit 15 (17) Initiate Configuration bit (IC). – When set (1), instructs the module to enter configuration
mode. Present configuration data prior to or coincident with IC being set. Once IC returns to 0,
the configuration is applied and any subquent configuration information is ignored until IC is
toggled.
(1) For changes in tag values like the CH bit in the IF4ICFXT to take effect, the tag either must be included in a ladder rung or or a configuration download forced using the
configuration tab in the RSLogix GUI.
Table 4.6
Word/Bit Descriptions for the 1794-IF4I Analog Input ModuleWrite
Write Word Decimal Bit (Octal
Bit) Definition