Reading Error Code from A1SHCPU

[despree 0]

Hello! I've been tasked with resurrecting an old deprecated project. Aren't those the best kind? We have a Melsec A1SHCPU that has a solid Error LED and a flashing RUN led when the key is turned to RUN. What I am trying to do is read the error code in the CPU register. What I've done so far: I cannot establish communications with it via the A1SJ71UC24-R2 module (though that module passes the loopback test), so I purchased an offbrand RS232-RS422 converter cable. I downloaded the trial version of GX Developer Version 8.68W from this site or a similar one.. and this is where I start to get into trouble. I am not able to set my PLC (that option is greyed out). I cannot start a new project (also greyed out). I *can* load a sample project, and one of those (Sample-2) will let me go to "Online->Transfer Setup". Changing the COM port to match that of my cable and setting the baud rate, I can press "Connection test" and it will reply back with a success message about talking to the A1SHCPU. So that's great; except, that doesn't match the version of the project; so any other function immediately get's met with "Connection error" because the PLC and the type for the project (which I can't change) don't match. So! Is this the best way to go about trying to read that error code? Can I get a project with the A1SHCPU set as the default so I can talk to my unit? Is there a different version of the software I can download to try, or buy? I was having a very, very hard time finding a non-trial version of the software available for download or purchase... Any advice or thoughts would be very, very appreciated!

[panic mode 246]

hmmm... first you need software that works and good cable to establish connection to PLC ... then you can read error. any way you can connect is fine.... can you try to go online directly with CPU?

[despree 0]

I can connect to it, so i've verified my cable is good. But the version of the demo software I have (GX Developer Version 8.68W) won't let me add a new project with my CPU, and so the software refuses to read any data from it.

[despree 0]

Update: I was able to find an A2SHCPU program example in the forum downloads. I found the type field in the .gpj, changed it to "A1SH", and my demo program is now allowing me to read error codes (woo!). First error code (32) related to another module; the 2nd related to the backup battery (being WAY dead; code 70); so I hooked up a power supply in place of the battery. The last error happens when I hit RUN, and is 12; "Missing END Inst." This really boggles my mind. Has anyone ever seen this just pop up one day when operating? My first thought is that when I disconnected the battery, something cleared? But it was so dead anyway, I have a hard time believing that. The second is that the actual ROM memory is going bad? I don't understand the memory structures of these devices well enough to know (there is not a cassette in the device, so I'm assuming programmed ROM memory). Anyone have experience with that error code, 12?

[stonesracing 0]

Hi there Despree, Did you get anywhere with the error code 12 issue as I am having the same issue with an A1s I am trying to get working on site at the moment. The detailed error codes given are 121, 122, 123 & 124 but I cannot find any information on these codes. Any help from anyone else is also greatly appreciated. Kind Regards, Ian

[Theo V 17]

Hi Despree, In the 'Manuals and Tutorials' I've uploaded the hardware manual for A-series CPU. Chapter 10 (starting from page 104) gives all kinds of information and flowcharts to identify (and solve) CPU problems. Best regards, Theo V.