Rockwell Automation 1794-APB/B FLEX I/O PROFIBUS Adapter Module User Manual - Manual (Page 65)

2–45 How Communication Takes Place and I/O Image Table Mapping
Publication 1794ĆUM057B-EN-P - November 2001
Word/Bit Descriptions for the 1794-OF4I Isolated Analog
Output Module
Read Words
Decimal Bit
(Octal Bit)
Definition
Word 1
Bits 00-15
(00-17)
Read Back Channel 0 - During normal operation, it is a copy of the output of
channel 0. During an EN transition, it is the condition of the output as
determined by S1 and S0. Read back is an image of what the user has sent
as output to the module; no checks are performed on the data.
Word 2
Bits 00-15
(00-17)
Read Back Channel 1 - During normal operation, it is a copy of the output of
channel 1. During an EN transition, it is the condition of the output as
determined by S1 and S0. Read back is an image of what the user has sent
as output to the module; no checks are performed on the data.
Word 3
Bits 00-15
(00-17)
Read Back Channel 2 - During normal operation, it is a copy of the output of
channel 2. During an EN transition, it is the condition of the output as
determined by S1 and S0. Read back is an image of what the user has sent
as output to the module; no checks are performed on the data.
Word 4
Bits 00-15
(00-17)
Read Back Channel 3 - During normal operation, it is a copy of the output of
channel 3. During an EN transition, it is the condition of the output as
determined by S1 and S0. Read back is an image of what the user has sent
as output to the module; no checks are performed on the data.
Bits 00 Reserved
Bits 01
CalibrationDone bit (DN). - This bit is set to 1 after a calibration cycle is
completed.
Bit 02
CalibrationBad bit (BD). - This bit is set to 1 if the channel calibration
coefficients cannot be saved or read properly.
Bits 03-07 Set to 0.
Bits 08-11
(10-12)
Reserved
Word 5 Bit 12 (14) Set to 0
Bit 13 (15)
Configuration mode bit (CF) - This bit is set (1) when the configuration
mode is selected (bit 15, word 5 in the block transfer write set to 1). When
this bit is set, the module status indicator flashes.
Bit 14 (16)
Field Power Off bit (FP) - This bit is set (1) when the 24V field power fails.
When this bit is set (1), the module status indicator flashes.
Bit 15 (17)
Power Up (unconfigured state) bit (PU). - This bit is set (1) when the
configuration word is all zeroes (0) due to a reset (adapter power cycle or
module insertion) or a cleared configuration word (all 0). When this bit is set,
the module status indicator flashes.
Bits 00-03
WireĆOff status bits. (W). - These bits, when set (1), indicate the
corresponding current output channel is open. W0 corresponds to channel 0,
W1 corresponds to channel 2, etc.
Bits 04-07 Set to 0.
Word 6
Bits 10-11
(12-13)
Hold output bits (P). - These bits are set (1) in response to Q0 or Q1 and a
transition of the EN bit. When P0 or P1 is set (1), they indicate that the output
is holding at the level in the readback data for the respective channel. These
bits return to 0 when the output data matches the readback output data.
Bits 12-15
(14-17)
Set to 0.