Manual

5–4 How Communication Takes Place and I/O Image Table Mapping with the DeviceNet Adapter
Publication 1794-6.5.7 – April 1997
00010203040506070809101112131415Dec. Bit
00010203040506071011121314151617Octal Bit
Read Word 7 Channel 5 Input Data
Read Word 8 Channel 6 Input Data
Read Word 9 Channel 7 Input Data
Read Word 10 Overrange Bits Underrange Bits
Read Word 11 0 0 0 0 0
Bad
Cal
Cal
Done
Cal
Range
0 Diagnostics
Pwr
Up
Bad
Structure
CJC
over
CJC
Under
Thermocouple/mV Input Module (1794-IT8) Write
Dec. Bit 15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
Octal Bit 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
Write Word 1 8-Bit Calibration Mask
Cal
Clk
Cal hi
Cal lo
Filter Cutoff FDF Data Type
Write Word 2 Thermocouple 3 Type Thermocouple 2 Type Thermocouple 1 Type Thermocouple 0 Type
Write Word 3 Thermocouple 7 Type Thermocouple 6 Type Thermocouple 5 Type Thermocouple 4 Type
Where: FDF = fixed digital filter bit
Word/Bit Descriptions for the 1794-IT8 Thermocouple/mV
Input Module
Word
Decimal Bit
(Octal Bit)
Description
Read Word 1 00–15 (00–17) Reserved
Read Word 2 00–15 (00–17) Channel 0 Input data
Read Word 3 00–15 (00–17) Channel 1 Input data
Read Word 4 00–15 (00–17) Channel 2 Input data
Read Word 5 00–15 (00–17) Channel 3 Input data
Read Word 6 00–15 (00–17) Channel 4 Input data
Read Word 7 00–15 (00–17) Channel 5 Input data
Read Word 8 00–15 (00–17) Channel 6 Input data
Read Word 9 00–15 (00–17) Channel 7 Input data
Read Word 10
00–07 (00–07) Underrange bits – these bits are set if the input signal is below the input channel’s minimum range.
08–15 (10–17) Overrange bits – these bits are set if 1), the input signal is above the input channel’s maximum range,
or 2), an open detector is detected.
Read Word 11
00 (00) Cold Junction sensor underrange bit. – this bit is set if the cold junction temperature is below 0
o
C.
01 (01) Cold Junction sensor overrange bit. – this bit is set if the cold junction temperature is above 70
o
C.
02 (02) Bad Structure – this bit is set if there is an invalid thermocouple type selected.