M4RTU/M4 I/O User’s Guide
75
TROUBLESHOOTING
Table A-1: M4RTU/M4 I/O Troubleshooting Chart
Indication
Condition/Problem
Action
RUN LED stays off.
Power not applied to processor.
Check power supply connections.
RUN light flashes.
Not enough power or malfunction.
Verify power supply voltage.
RUN LED flashes after a kernel
(firmware) is downloaded or power
failure occurred during EEPROM
firmware installation.
Kernel (firmware) is corrupted.
Remove Boot Loader jumper so that
M4RTU/M4 I/O boots to loader. Reinstall
EEPROM firmware, then reinstall Boot Loader
jumper.
TX0 (COM0 transmit) LED stays off.
Port not transmitting.
Cycle power to unit. Check CTS connection;
must be connected to RTS if not used. Check
jumper settings and/or controller
communications setup.
RX0 (COM0 receive) LED stays off.
Port is idle.
Wire or connection is bad.
Check wiring for polarity transposition.
Check connections at terminals.
Host does not receive a response
from the M4RTU/M4 I/O, and RX0
or RX1 (COMO or COM1 receive)
LED flashes communications setup,
during program download.
PC to M4RTU/M4 I/O connections
are incorrect.
Incorrect setup in the OptoControl
controller configurations.
Check wiring connections for correct polarity
and wire integrity.
Check controller configurations; specifically
baud rate, address, and binary/ASCII settings.
TX1 (COM1 transmit) LED stays off.
Port not transmitting.
Cycle power to unit. Check jumper settings
and/or controller communications setup.
RX1 (COM1 receive) LED stays off.
Port is idle.
Wire or connection is bad.
Check wiring for polarity transposition.
Check connections at terminals.
M4RTU/M4 I/O controller cannot
transmit to PC.
Configuration jumpers were
changed without cycling power.
Wiring to serial port is incorrect.
Cycle power and retry transmission.
Check wiring for possible polarity transposition.
Digital output is not working.
Bad module fuse.
Wrong module type. Incorrect
wiring.
Replace fuse.
Make sure module is 5V (G4ODC5 is correct,
G4ODC24 is incorrect) Match the output
module with the load. Use G4SWOUT module
to troubleshoot. If G4SWOUT works, contact
Opto 22 Product Support (see Appendix G).
Output does not work with
G4SWOUT module installed.
Load does not work with voltage
applied. Output is wired wrong.
Check field wiring worksheets (see Appendix F)
and rewire, if necessary.
APPENDIX A
Summary of Contents for Modular M4RTU
Page 6: ...6 M4RTU M4 I O User s Guide TABLE OF CONTENTS...
Page 74: ...74 M4RTU M4 I O User s Guide FIELD WIRING...
Page 80: ...80 M4RTU M4 I O User s Guide PRODUCT SPECIFICATIONS...
Page 82: ...82 M4RTU M4 I O User s Guide ADDRESS JUMPER CONFIGURATION...
Page 86: ...86 M4RTU M4 I O User s Guide UPGRADING RAM AND FLASH EEPROM...
Page 89: ...M4RTU M4 I O User s Guide 89 WORKSHEETS Figure F 3 M4RTUX I O Extender I O Module Worksheet...
Page 91: ...M4RTU M4 I O User s Guide 91 WORKSHEETS Figure F 5 Field Wiring Worksheet Example 2...
Page 94: ...94 M4RTU M4 I O User s Guide WORKSHEETS...
