"Media test failure, check cable" and "Plug is missing" errors?

AirWolf

AirWolf

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Hi all

At work I'm having a problem with the connection between a pc and a circuit board.

When the pc starts up it gives the following:
PXE-E61 Media test failure, check cable.
PXE-M0F Exiting Intel Boot agent.
Click to expand...

The pc has a PCI card with a female COM port. The PCI card is connected to the circuit board via a 5metre serial cable (male to male). A network connection is created, but there doesn't seem to be any data flow.

The pc is used to control valves/pumps etc in a chemical plant. When I start the program that uses the connection, it gives me the following error:
Warning:
Plug is missing.Therefore you will work on a demo model. Some features will not have full functionality. Network is disabled.
Click to expand...

The cable does not appear to be damaged. When I unplug the cable from the circuit board, it does give me a communication error, but when it is plugged in I am still unable to control any plant equipment nor receive any data reading regarding valves open/closed etc.

I'm having a bit of trouble sourcing a new cable. Where can I get one?

Is there anything else that might be causing the problem?

(This pc is not connected to the internet; we do not have admin rights on the machine - can't install new hardware).
 
I cannot help you unless you tell me what equipment this is. This sounds like SCADA/Process control.

Are these National Instruments' cards? A photograph would also be helpful.

This error:
PXE-E61 Media test failure, check cable.
PXE-M0F Exiting Intel Boot agent
Click to expand...
is from the BOOT ROM code in the network card. I assume this PC has a LAN card, which in all possibility is causing this problem.
 
Turiko said:
I cannot help you unless you tell me what equipment this is. This sounds like SCADA/Process control.

Are these National Instruments' cards? A photograph would also be helpful.

This error:

is from the BOOT ROM code in the network card. I assume this PC has a LAN card, which in all possibility is causing this problem.
Click to expand...

This is a SCADA/Process control system. I think the PCI card in the pc is a National Instruments (will confirm tomorrow and try to get a pic as well). The PCI card with the female COM port is the network card. (No cable plugs into the onboard lan port).
 
PXE - preboot execution enviroment, commonly know as pixie boot, your network card has the ability to boot and load a MS OS (xp onwards) from a RIS - remote installation server or now known as a WDS server where operating system images are stored.

You can turn this Lan card function off in your bios, it will say ' enable pxe boot' or 'enable lan for PXE'

PXE-M0F Exiting Intel Boot agent - the card starts and then loads a little boot app which allows the card to go and seek out a RIS/WDS server on the network, nothing to worry about, just let it run through the motions, it harmless and will cause no interference.
 
Yes I am familliar with that card. This appears to be an electrically isolated RS232 interface card.

Have you tried the following:

1. Ensure correct drivers are loaded
2. Open HyperTerminal, select, say 1200bps 8N1, no handshaking.
3. Short pins 2 and 3 with a screwdriver
4. type on the keyboard, it should all echo back to you
 
Turiko said:
Yes I am familliar with that card. This appears to be an electrically isolated RS232 interface card.

Have you tried the following:

1. Ensure correct drivers are loaded
2. Open HyperTerminal, select, say 1200bps 8N1, no handshaking.
3. Short pins 2 and 3 with a screwdriver
4. type on the keyboard, it should all echo back to you
Click to expand...

I only see the characters on the screen when I have the ASCII setup option:"Echo typed characters locally" ticked.
 
Saule said:
I only see the characters on the screen when I have the ASCII setup option:"Echo typed characters locally" ticked.
Click to expand...

That means you're doing a software loopback.... so you shouldn't tick that option. If you shorted 2-3 you should have seen the characters come back to you on the screen. Do you have an oscilloscope? If so, check what happens on the pins when you type a character

What COM port does this device come up as on the PC?

Please give me the exact model number so I can do some reading up in the meantime.
 
Turiko said:
That means you're doing a software loopback.... so you shouldn't tick that option. If you shorted 2-3 you should have seen the characters come back to you on the screen. Do you have an oscilloscope? If so, check what happens on the pins when you type a character

What COM port does this device come up as on the PC?

Please give me the exact model number so I can do some reading up in the meantime.
Click to expand...

The only port that comes up is COM1 (the other option is TCP/IP). I don't have an oscilloscope.

The PLC is a Simatic S7 400.
 
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