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Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 5 Power On Self Test (POST)
Critical
A critical hardware fault indicates that the device does not pass critical self-test
checks, therefore ISDU communications is not possible. In this scenario, the
result codes are communicated using the device status indicator only.
Severe
A severe hardware fault indicates that the device passes a minimal set of power
on self test checks allowing execution of its application firmware and
processing of ISDU commands. In this scenario, the result code is
communicated via 'Power On Self Test Status' ISDU command and the POST
alarm is raised via Alarm Status variable. The device status indicator also
communicates this fault.
Device Status Indicator -
Error Codes
When the firmware of the device detects an error condition, the error code is
communicated by blinking the device status indicator red in the following way:
<start pattern>, <1 s OFF>, <binary error code>, <2 s OFF>, <repeat>
<start pattern> = 100 ms ON, 100 ms OFF, <repeat four more times>
where:
<binary error code> = 4-bit error value, where a 1 is 1 sec ON, and a 0 is
500 ms ON. Each bit is separated by a 1 sec OFF.
The value of the binary error codes are shown in
(for
example, RAM test failed is 0101.)
Figure 7 - Error Code Status Indicator Example
IO-Link Status Indicator
Timing
The IO-Link status indicator is normally in the ON state. Communication
activity turns off (T
off
) the green indicator for a minimum of 7.5% but no more
than 12.5% of the duty cycle (T
rep
). The minimum status indicator ON time
(T
rep
) is 750 ms, and the maximum ON time during activity is 1250 ms. Each
(T
rep
) period begins in the OFF state.
Figure 8 - Status Indicator Timing
Start pattern
100ms ON
100ms OFF
Repeat
1 s
500 ms
0
1
0
1
1 s
1 s
1 s
1 s
2 s
100ms ON
100ms OFF
Status Indicator On
Status Indicator On
Status Indicator On
Status Indicator
Off
Status Indicator
Off
T
off
T
rep
Содержание Allen-Bradley 856T-B24LC
Страница 6: ...6 Rockwell Automation Publication 856T UM001B EN P April 2021 Table of Contents Notes ...
Страница 18: ...18 Rockwell Automation Publication 856T UM001B EN P April 2021 Chapter 2 IO Link Overview Notes ...
Страница 72: ...72 Rockwell Automation Publication 856T UM001B EN P April 2021 Appendix D Device Status Notes ...
Страница 76: ...76 Rockwell Automation Publication 856T UM001B EN P April 2021 Appendix F Troubleshooting Notes ...
Страница 80: ...80 Rockwell Automation Publication 856T UM001B EN P April 2021 Index Notes ...