Allen-Bradley FLEX I/O 1794-IJ2, Руководство пользователя, Страница: 45 / 80

Publication 1794-6.5.11 - November 1997
Writing Configuration to and Reading Status from Your Module with a Remote I/O Adapter 4 -7
Word 0
cont.
Bits 05
Frequency range bits (channel 1) – Specifies the Frequency Range of the Frequency input.
0 = 1-32767 (below 1Hz reports 0);
1 = 1.0-3276.7 (below 1.0Hz reports 0.0).
Default = 0
Bit 06
Local fault mode selection – determines how the Module Safe State data will be used to control alarm outputs for bus
communication and internal module faults (local fault = Wire Off Fault or Missing Pulse Alarm).
0 = safe states activated by bus communication only;
1 = safe states activated by any failure (bus communication, internal module faults, etc.)
Default = 0, safe states activated by bus communication only
Bit 07 Not used
Bits 08-09
(10-11)
Missing pulse multiplier bits (channel 0)– used to modify the Minimum Frequency Sampling Time to allow the frequency
bandwidth to be more closely adjusted to the value needed to report the proper frequency and report a missing pulse
more quickly.
Default = no multiplier; alarm generated immediately
Bit
09
(11)
08
(10)
Minimum frequency sampling time
0 0 No Multiplier, alarm generated immediately (normal mode with 2s delay)
0 1 X2
1 0 X8
1 1 X32
Bits 10-12
(12-14)
Number of pulses to terminate sampling (channel 0) – Lets you calculate Frequency when a specified number of input
pulses have occurred. This allows earlier reporting of the frequency than the Minimum Frequency Sampling Time, when
many input pulses are occurring. Accurate frequency determination is possible without waiting for the full Minimum
Frequency Sampling Time to expire.
Defaul t = minimum frequency sampling time.
Bit
12
(14)
11
(13)
10
(12)
Number of pulses to terminate sampling
0 0 0 Use minimum frequency sampling time
0 0 1 2
0 1 0 4
0 1 1 8
1 0 0 16
1 0 1 32
1 1 0 64
1 1 1 128
Word 0
cont.
Bit 13 (15)
Frequency range bits (channel 0) – Specifies the Frequency Range of the Frequency input.
0 = 1-32767 (below 1Hz reports 0);
1 = 1.0-3276.7 (below 1.0Hz reports 0.0).
Default = 0
Bit 14 (16)
Safe state mode bit – selection determines how module alarm outputs react to bus communication and internal module
faults (local fault = Wire Off Fault or Missing Pulse Alarm).
0 = Reset outputs
1 = Hold last state
Default = 0 (reset outputs).
Bit 15 (17)
Communication fault – Signals the module that communications has been interrupted on the network. The adapter
signals that the module should execute its fault routine or go to the Safe State and control any Alarm Outputs accordingly.
During normal startup, this bit must be set (1) by the user program to begin normal module operation of Alarm Outputs (in
effect, an output enable). When the adapter communication link is broken, the adapter will reset this bit (0).
– (Adapter
dependent.)
Default
= 0.
Word Bit Definition
Allen-Bradley Replacements