Rs232 to SLC 5/03 Problem

YorkMa

Member
Join Date
May 2017
Location
Toronto
Posts
8
hello everyone,
im having a problem to connect one of slc 5/03 with rs232 to my laptop. i rslinx it and keeps showing me "fail to find the baud and parity". i use com1,and tried different settings as online info i got still cannt make it to work. but same settings i tried on other slc5/03 or 5/04 they work totally fine,that tells me my port on my computer and the rs232 are ok right? but what else i can change on settings to connect? like device is slc-ch0/micro/panelview,error checking CRC,just cannt pass auto-config.
can someone pls save me from pulling out all my hair.
 
Do you know how the port on the SLC is configured?

DF1, DH485 or ASCII protocol ?

If you have the offline program check the channel configuration.

Or post the .RSS file here ( zip it first) and someone will help.
 
Is this a working PLC?

If not you could reset the processor to default condition by removing the battery and shorting out VBB to GND See pdf below. Be advised this will clear the memory. So if this is a working PLC and you don't have a backup of the program don't do it.

Was there anything connected to the serial port?

Do you have any other hardware to try DH485 protocol. (1761-NET-AIC, 1747-PIC, 1747-UIC)
Or get connected to the DH485 port?
 
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Hi and welcome to the Forum!

Geospark said:
...for non defaulted SLC controllers where you know Channel 0 is in use...

To tell which protocol Channel 0 is set for, unplug any cable, and watch the RS232 LED...

If it remains Off, then it is set for DF1

If it flashes slowly then it is set for DH-485...

Note: It flashes when set for the DH-485 protocol because the controller port is cyclically polling the DataHighway-485 network.

The port could also be set to "Shutdown" under the "Chan. 0 - System" tab. This is sometimes used when communications are only intended to be made through the fixed Channel 1 DH-485 port. For "Shutdown" to work, you must also set the "Driver" field under the "Chan. 0 - User" tab to "Shutdown". This disables both the System and the User setting for the port.

On the other hand, if the "Chan. 0 - System" tab is set for "Shutdown" and the "Chan. 0 - User" tab is left set to the ASCII protocol, then the port is most likely intentionally configured to use the ASCII protocol. If this were the case, then I would imagine that the Channel 0 port is, or was, connected to something that communicates in ASCII?

Is the controller keyswitch in RUN, REM or PROG Mode?

What are the other LED indicators doing?

If the RS232 Channel 0 port is configured for the DH-485 protocol (RS232 LED flashing) then you will need to use the likes of a 1747-UIC interface converter.

This is a USB to Serial interface which will convert DF1 protocol to DH-485 protocol.

As a "by the way", do you have a 1747-UIC to hand?

Is the Channel 1 DH-485 port free or in "use"?

EDIT: I just posted Mickey. I didn't see your most recent thoughts. Apologies for any duplication, but great minds and all that...

Regards,
George
 
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Thank you guys so much for the reply.
Yes it is a working PLC. And I only have rs232 interface working. I do have a 1747-PIC one end is DH485 the other end is rs232 but I haven't figured out where I can get a driver for windows7/32 yet . I guess I need to get that to work to solve the problem. Any suggestions?
 
Slow and steady here - Who said it's set for DH-485???

YorkMa said:
Thank you guys so much for the reply.
Yes it is a working PLC. And I only have rs232 interface working. I do have a 1747-PIC one end is DH485 the other end is rs232 but I haven't figured out where I can get a driver for windows7/32 yet . I guess I need to get that to work to solve the problem. Any suggestions?

One suggestion I could make, as you are new here, is that you pay careful attention to the advice we are giving and the questions we are asking you. We are here to help but our time is as important as anyone's.

If we ask a specific question or give you specific instructions, and you don't attempt to answer them or carry them out, then we can end up either having to ask them again, or as may be the case here, potentially heading down the wrong path.

You have been asked what protocol is the port using and you have said that you do not know. You have been given a simple method to ascertain which protocol it may be configured for, but without answering as to whether you have even checked, or not. Perhaps you have checked? But you have not intimated as such to us.

Other specific questions have also not been answered...

"...it is a working PLC..." does not tell us what position the key switch is in. Nor does it tell us what the LED indicators are doing. It also does not tell us if the Channel 1 DH-485 port is in use, or not.

We are now discussing how to get a 1747-PIC DH-485 interface converter up and running in Windows 7. An interface which can be notoriously difficult to master, even in its compatible Windows XP environment.

So, once more...

With no cable in the RS-232 Channel 0 port...

Is the RS232 LED indicator Off? - DF1 (most likely, but not definitely)

Or...

Is the RS232 LED flashing slowly? - DH-485

Is the controller keyswitch in RUN, REM or PROG Mode?

What are the other LED indicators doing?

Is the Channel 1 DH-485 port free or in "use"?

I was asking if you had a 1747-UIC interface "to hand" because it would be a relatively quick and easy test for the DH-485 protocol. You do not have one so I would not start off down the DH-485 path just yet until you confirm the RS232 LED indicator suggests it is using this protocol.

Having said that, I would always advise users to carry a 1747-UIC, or two (I have three), when dealing with legacy DH-485 equipment. So I would follows Mickey's good advice, and link, and get yourself one regardless of the outcome here.

Regards,
George
 
Thank you guys so much for the help and your time, pls for give me if I miss understood or couldn't answer any question to eliminate the problem that's because I'm an true plc newbie not because I have no respection. I'm so so sorry for causing this.
Because I can't connect the plc and I don't have offline backup program so I don't know how to figure out if the port is DF1 or DH485 or ASCII . And when I mention it is a working plc is because Micky told me there's a way to reset the processor module if it not a working plc and I have a backup program.
And I do apologize that I didn't mention the key position, because I tried all 3 run, rem, and prog position and didn't see any progress.
And for the indication light, is DH485 flashes slowly. But few days ago I have another plc running with DH485 flashing, I thought I had to use DH485 but surprisingly I connected with same rs232 cable.
So, on channel 0, the DH485 port is in use to a controller and RS232 port is empty. And DH485 light is flashing slowly and no rs232, no fault.the key is on run, but I tried on rem and prog too.
I'm trying to order a 1747-UIC, before I get it, is there anything else I can try?
For sure first thing tomorrow morning I will go and unplug the cable on pot Dh485 as George mentioned to see if Rs232 will flash.
My laptop does have a 9pin rs 232 port, is that what you mean by a real serial port? But from the link my understanding is no matter what, 1747-pic I have just can not work with windows 7 right? So I'm gonna have to wait for 1747-uic I guess.
Thank you so much to George and Micky for the help with my poor plc knowledge I hope I don't confuse you guys too much. I sincerely appreciate you.
 
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hi George, i tried the Slc 5/03 i cannt get connectionbefore i unplug anything,the pls is on running mode,key in on run,indication is running and DH485 solid on,port DH485 is connected to controller screen, port rs232 is empty. and i unplug the DH485,nothing change except the DH485 indication flash slowly,rs232 stays dark. and i also tried with different key positions, only change is the run indication.
we also have another machine same processor module same port connection but i can connect with rs232 and check settings and channel 0 system is DF1 full duplex,i tried unplugging and key positons,act same as the one i cannt make the connection.
i tried on a third plc with same processor module and this one both DH485 and RS232 ports are empty with channel 0-system sets as DF1 full duplex, indication acts same.
i cannt see any difference. is there anything else i can try before i get a 1747-uic? thank you very much
 
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Im not George (my answers are a lot shorter) :) but.... if I were you I would by a UIC unplug the HMI and upload the program, you can then change the RS232 port to just standard or verify its default and either change it or download to another PLC and then you can use the CP3 cable for normal COMMS

Buy this kit, use overnight shipping https://www.plccable.com/allen-bradley-1747-uic-usb-1747-cp3-1761-cbl-pm02-1756-cp3-programming-set/

Then watch the videos https://www.plccable.com/support-videos-compatibility/

And tomorrow AM you can be up and running
 
geniusintraining said:
Im not George (my answers are a lot shorter)...

Mark,

You are more of a "get you there guy", whereas I am more of a "guide you there guy". That's all.

----------------------------

YorkMa,

I would definitely be getting that 1747-UIC. Going in through the Channel 1 DH485 port would have been my advice once we had exhausted all options on the Channel 0 RS232 port.

So, while we await that interface...

When I read your comments I still notice some small discrepancies in how you are viewing and understanding what is what here?...

Let's see what we can ascertain or clear up here...

YorkMa said:
...hi George, i tried the Slc 5/03 i cannt get connectionbefore i unplug anything,the pls is on running mode,key in on run,indication is running and DH485 solid on,port DH485 is connected to controller screen, port rs232 is empty. and i unplug the DH485,nothing change except the DH485 indication flash slowly,rs232 stays dark...

You appear to be a bit mixed up in what the LED indicators represent here. Also, there may be some confusion between the terms "DH485" and "RS232". And also, which port we are referring to having no cable plugged in. So I will lay it out for you so you can be more sure of what you are seeing and what you think you should be seeing...

SLC 5/03 communications ports...

Channel 1:

The top Channel 1 port is physically an RJ45 connector. It uses the RS-485 wiring standard. It is fixed to the DH-485 communications protocol. The sticker on the door beside the port says "DH485", which denotes which protocol this port is fixed to, and not which wiring standard it uses. The LED marked "DH485" indicates the status of Channel 1 only.

Channel 0:

The bottom Channel 0 port is physically a 9-pin D-subminiature (DE-9) male connector. It uses the RS-232 wiring standard. It can be set for DF1, DH-485, or ASCII communications protocol. The sticker on the door beside the port says "RS232", which denotes which wiring standard this port is fixed to, and not which communications protocol it uses. The LED marked "RS232" indicates the status of Channel 0 only.

That, hopefully, explains the difference between references to wiring standards and protocols used on these ports, how the ports are labelled and "where" their status is indicated.

Now for "how" their status may be indicated...

From your information above, the Channel 1 "DH485" port is communicating with a terminal of some sort which must also be using the DH-485 protocol. When you unplug the cable from the top Channel 1 port the "DH485" LED indicator will flash slowly as the DH-485 protocol will cyclically poll the network. When you plug the cable back into Channel 1, and communications are re-established with the terminal, the "DH485" LED indicator will be permanently ON, indicating good and active communications on that port.

When you unplug the cable from Channel 1 "DH485", it will only influence the status of the Channel 1 "DH485" LED indicator. It will not influence the status of the "RS232" LED indicator.

The "RS232" LED indicator signifies the status of communications for the bottom Channel 0 "RS232" port. When this port is at its default settings it is configured to use the DF1 communications protocol. When using DF1, and no cable is plugged into the bottom Channel 0 "RS232" port, the "RS232" LED indicator will be permanently OFF.

DF1 communications to Channel 0...

If you successfully communicate to the controller using the "RS232 DF1 devices" driver in RSLinx Classic, then the "RS232" LED will rapidly flash twice and then OFF in a cyclical fashion. This is just the driver maintaining basic communications with the controller.

If you stop the driver or plug the cable out, then the "RS232" LED will again be permanently OFF.

If you successfully Go Online to the controller in RSLogix 500, using the DF1 driver, then the "RS232" LED will now continuously and rapidly flash. This is because full communications have now been established between the controller and the programming software.

If you Go Offline or plug the cable out, then the "RS232" LED will again be permanently OFF.

To recap...

When using DF1 on the Channel 0 "RS232" port and no cable is plugged in, then the "RS232" LED will be permanently OFF.

When any type of DF1 communications are established with Channel 0 then the "RS232" LED will flash in one pattern or another. At no point, while communicating using the DF1 protocol, will the "RS232" LED remain permanently ON. This is how the "RS232" LED indicator operates when Channel 0 is configured to use the DF1 protocol.

DH-485 communications to Channel 0...

If the Channel 0 "RS232" port has been reconfigured to use the DH-485 protocol, and no cable is plugged into the port, then the "RS232" LED indicator will flash slowly, as the DH-485 protocol will cyclically poll the network, looking for nodes to communicate with. When you plug a cable into Channel 0, and communications are established with a DH-485 device, or network of devices, then the "RS232" LED indicator will be permanently ON, indicating good and active communications on that port. This is how the "RS232" LED indicator operates when Channel 0 is configured to use the DH-485 protocol.

To recap...

When using DH-485 on the Channel 0 "RS232" port and no cable is plugged in, then the "RS232" LED will flash slowly.

When any type of DH-485 communications are established with Channel 0 then the "RS232" LED will remain permanently ON. At no point, while communicating using the DH-485 protocol, will the "RS232" LED flash. This is how the "RS232" LED indicator operates when Channel 0 is configured to use the DH-485 protocol.

Basically, the Channel 0 "RS232" LED behaves the same as the Channel 1 "DH485" LED when Channel 0 is configured to use the DH-485 communications protocol.

Right, where were we?...

YorkMa said:
...i unplug the DH485,nothing change except the DH485 indication flash slowly,rs232 stays dark...i also tried with different key positions, only change is the run indication...

So we are clear - In previous posts I was not suggesting, at any point, that you unplug a cable from the Channel 1 port. I was describing what the Channel 0 "RS232" LED indicator should do when set for a particular protocol and there is no cable plugged in.

I was also not suggesting that you change the key switch position. I was only asking which position it is currently in.

But seeing as you were doing so - when you are unplugging the cable from the Channel 1 "DH485" port, it will not have any effect on the Channel 0 "RS232" LED indicator, as I have explained above. If the "RS232" LED is permanently OFF, with no cable connected to Channel 0, then it is most likely that the Channel 0 "RS232" port is currently configured for the DF1 protocol. But that is not a definite conclusion.

The 1747-UIC will not establish a connection to the Channel 0 port unless it is flashing slowly, signifying it is configured for the DH-485 protocol. You will, as we have mentioned, be able to establish a connection to the Channel 1 port, as this port is fixed for the DH-485 protocol.

But, if the Channel 0 "RS232" LED is permanently OFF, suggesting DF1, then what are the bets that, when you Go Online through Channel 1 using the 1747-UIC, Channel 0 will be configured for the default DF1 settings? Where will that leave you? You will only have confirmed that it is set as the LED indicator suggests it is. If this turns out to the be the case, then that just brings us full circle to the issue as it stands now...

Why can you not establish a connection to the Channel 0 "RS232" port when it "appears" to be configured for DF1? There is still the possibility that the port has either been set to User ASCII protocol or has been "Shutdown". If either are true, then the "RS232" LED indicator will also be permanently OFF.

YorkMa said:
...we also have another machine same processor module same port connection but i can connect with rs232 and check settings and channel 0 system is DF1 full duplex,i tried unplugging and key positons,act same as the one i cannt make the connection.
i tried on a third plc with same processor module and this one both DH485 and RS232 ports are empty with channel 0-system sets as DF1 full duplex, indication acts same. i cannt see any difference...

You could have ten SLC 5/03 processor to check and they may all display the same status on their "RS232" LED, but it does necessarily mean they will all be set the same for their Channel 0 port. As I'm sure you are now realizing, the Channel 0 "RS232" LED being permanently OFF, with no cable connected, can mean any of three normal configurations for this particular port...

DF1
ASCII
Shutdown

I have made a couple of "quick" videos (sorry for the camera shake!) to demonstrate the operations for the LED indicators when the Channel 0 port is set for DF1 or DH-485...

Video: SLC_5_03_Port_Status_CH0_DF1

Default Communications
No cables connected

Channel 1 DH-485 - "DH485" LED Flashing Slow
Channel 0 DF1 - "RS232" LED Permanently OFF

------------------------------------------------------

Video: SLC_5_03_Port_Status_CH0_DH485

Channel 1 DH-485 - communications established
Channel 0 DH-485 - no cable connected

Channel 1 DH-485 - "DH485" LED Permanently ON
Channel 0 DH-485 - "RS232" LED Flashing Slow

Any update on the 1747-UIC delivery? I am really curious to know the outcome here?...

Regards,
George
 

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