OLD Mitsubishi A0J2

[Dariusch]

I have a problem with an A0J2-PLC. I was called out to a customer who has a machine with an A0J2-PLC. First there was no power to the PLC, I turned the power on, but then the "RUN"-led flashes slowley. I tryed reset but it did not help. The I tryed to communicate trouht GX-Developer, but could not because it dosent support the OLD PLC. Then I tryed with Medoc 2.3, but I did not get any response from the PLC. My conclusion is: 1) The CPU is dead or 2) I can not communicate with my laptop running Win XP. Please can some one help me on this one!?!? If You also thin the CPU is dead, maby you could tell me where to get this old CPU. My lokal mitsubishi reseller can not help me. (tells me that I have to replace with new). Thank you Dariusch

[JimRowell]

For starters, you need the programming manual. It has a troubleshooting section in it that may help. You can get it here: http://www.meau.com/Files/IB_NA_66057-C.PDF Also the user's manual: http://www.meau.com/Files/IB_NA_66058-D.PDF I don't know too much about this series but I do know that it can have battery backed program memory. If the power was off to the machine and the battery was dead and the progam was stored in ram... there is no longer a program in the plc. Regardless, you should be able to connect to it. Check the manuals for the appropriate cable and procedure for comm. You need the manuals anyway even if someone else can help you more directly. Don't open up GX or any other software while you are trying to communicate with the plc via Medoc. Its not unusual for programs to lock up a port while they are running (Medoc itself does). Make sure the comm settings are correct in Medoc. If you need help on that, let me know. Jim

[Dariusch]

Hi Jim and Thank you for your quick response. I have read the manual (thank you again for the link), but I can not see the error-code at the PLC, since I can not communicate with it. My com. setup in medoc is: PLC: A0J2 Bit rate: 9600 Word length: 8 Parity: Odd Stopbits: 1 Port: Com 1 That should be right dont it?? Could it probably be the XP, that cuts me of the PLC?? Can one get a real DOS-prompt in XP? Thank you again Dariusch

[JimRowell]

Dariusch, I wrote a quicky utility for you to try (its attached to this reply). All it does is send a simple enquiry to the plc. If it doesn't work, it doesn't prove anything. If it does work, then you should be able to communicate with the appropriate software. It should work fine in XP. Just make sure the Port and other settings are right and click on Send. Its under a meg. Not too long a download and does NOT require any sort of installation. Just double click on the file to run. Simply delete it at any time it if you wish. Jim Hello.zip

[Dariusch]

Hi Jim Thank you again for your help. I will try your util. tomorrow Dariusch

[Paul416]

I've tryed several times to get medoc to work with XP but though the program will run it always fails on comms.

[Guest aguirRe]

MEDOC DOS works in almost any DOS environment, real or emulated. However, to communicate with the A-series via the CPU-port under NT/2K/XP, you may need to add command line option Fn (e.g. "MEDOC F10"). The value "n" introduces a delay and may be tweaked up or down for best results depending on computer speed and acceptable delays. This is a workaround for the NTVDM (which MEDOC DOS runs under) being unable to carry out precise UART control from DOS-applications. This in turn is required for the A-series CPU-protocol to work properly. MEDOC 32-bit does not have this limitation but is currently limited to distribution in Scandinavia.

[navillusi]

I have always had to carry round two laptops, one old one for medoc and one new one for everything else - now my back will be feeling better!! Excellent piece of information Cheers

[Guest aguirRe]

Slightly off-topic, but I think I recall reading about problems using MEDOC through a modem, i.e. having to use another tool for the actual dial-up process. Starting with version 2.10, MEDOC has the ability to make use of a project modem file (e.g. PROJECT.MDM) for the dial-up commands. It's just a standard text file that should contain the modem commands necessary to make the call, one command for each line and the last line having the ATDT command. If this file is present for the currently opened project (in the same directory), it will be used for dialling before any PLC communication starts. When closing the comm port, MEDOC will automatically hang up the modem. To disable this behaviour, just move or rename the modem file.