Home » Categories » Protocols » Modbus |
My RX light is on solid, what might that indicate? |
Article Number: 561 | Rating: Unrated | Last Updated: Fri, Jul 17, 2015 at 10:32 PM |
If the RX light is on solid on your modbus serial port and: The port is in RS485 mode- This is usually indicative of polarity being reversed (ie. positive is connected to negative instead of positive to positive). Try swapping the wiring to pins 1 and 8 on our port. The port is in RS232 mode- This suggests that a constant electrical signal is hitting our receive pin which should never occur during normal operation. We have seen this on occasion with customer USB to serial converters which are not set up correctly, we strongly recommend trouble shooting your USB to serial converter if this is the case. If there is no converter involved, we recommend verifying the wire connected to our RX pin is connected to the correct pin on the other device. If none of these common causes seem to be causing your RX to be on solid, please call Prosoft Technical Support to trouble shoot your issue further. |
Attachments (0)
There are no attachments for this article.
|
Comments
There are no comments for this article. Be the first to post a comment.
|
Why are my PLX gateway modbus serial commands not executing despite being enabled?
Viewed 1 times since Wed, Aug 12, 2015
How do I read/write Modbus binary data?
Viewed 1 times since Wed, Nov 29, 2006
I am trying to use a ProSoft Modbus solution to send/receive data to a MSA Ultima X gas dectection system with Modbus interface and am having problems. How can I resolve this issue?
Viewed 1 times since Thu, Apr 24, 2008
Why is the bit or coil level data incorrect?
Viewed 1 times since Tue, Nov 28, 2006
What Modbus address would we need to put into the MODSIM32 simulator if we specified on the MVI56-MCM device address to 8680HEX (-31104 decimal) when the MVI56-mcm is the slave?
Viewed 1 times since Tue, Nov 28, 2006
How do I enter a Modbus address of 40001 or higher in the DevAddress command field of my MVI56-MCM?
Viewed 1 times since Tue, Nov 28, 2006
Do any Prosoft modules support Modbus UDP?
Viewed 1 times since Mon, Aug 24, 2015
I have a ProSoft Modbus Master solution and would like to know, is the Slave Status List the best place to monitor for communications health of the network?
Viewed 1 times since Tue, Mar 18, 2008
If I am reading the value from ProSoft 4x register, and it represents a digital input or digital output, how is the value stored?
Viewed 1 times since Tue, Nov 28, 2006
Defining the Slave ID when issuing Modbus Broadcast write commands
Viewed 1 times since Tue, Nov 28, 2006
|