Trying to download program from Mitsubishi A172SHCPUN fails

[lbcobra]

Hi,


New to the forum.


I have an old machine I am working on that is using aA172SHCPUN. I want to capture the program in case I need to reload it if something goes wrong.



I've downloaded GX Works 2 and GX Developer. I believe current versions. In GX Developer I can connect to the PLC and download the memory, but it won't allow me to download the program. (I'm writing this from memory as everything is at the shop.)



I selected ACPU and A2SHCPU. When I try and download the program it give me an error that says that the "memory capacity settings (main capacity) set in the parameters and the memory capacity in the PLC do not match."


Is it possible that the PLC is somehow locked and does not allow me to download the program?



What else can I try?


Thank you


len

 

[parky]

create a new project, in the tree on the left hand side select PLC Parameter then memory capacity & try changing the Sequence (Main to a larger value ) then try to upload all not just the program, don't have an A2 but another alternative is to upload the PLC parameters only to the new project & that may overwrite the default settings then upload I also suggest you upload the device memory, this will also give you a snapshot of the D registers that may contain data as it's current state.

 

[parky]

Just as a matter of interest, depending on what IDE was used for the program will depend on the logic you will get uploaded. For example if GX Developer was used then strait forward ladder, however, if it was done in GXIEC (Early version of GXWorks) then the code will translate to ladder but you may find there are loads of calls to subroutines (although one large ladder program there will be an FEND after the main scan & calls to sub routines with pointers to those) also there will be loads of temporary memory addresses used this is to format the FBD style in GXIEC.
On that IEC platform there was also a possibility of what seems like errors i.e. ladders that did not connect but actually worked or maybe even will not display in ladder but in statement list only.

 

[parky]

Ah... Just realised this is a motion CPU you need to select Motion CPU then A172shCPU then try It is not a A2.
Even if you use GXWorks it will load a compatible version of GXDeveloper

 

[lbcobra]

Ok, will try and create a new project and set the parameters for a larger memory. I will be in the shop again tomorrow.



I will report my findings. Thank you for your suggestions.


len

 

[parky]

You say you selected an A2 cpu that is not the same if you select motion then it will display the correct CPU i.e. A172SH

 

[lbcobra]

I selected Series ACPU TYPE A2SH(S1)


I don't have A172SH listed in the drop down.



Running 1.596W trial version GX Works
GX Development Version 8.98C

 

[parky]

I have GXDev 8.5 an it contains the motion CPU see pic.
you cannot use A2 version for a motion CPU but you having a later version should contain the older motion CPU.

 

[lbcobra]

Found it! Awesome, thank you


len

 

[lbcobra]

I'm still having issues in downloading the program. Like before I can read the device memory, but the our come seems rather small, I think 1024 bytes.


When I go into the PLC parameters and set the memory size I still get the error. I tried 1 sequence of 58k and 6 sequences of 2k and got the same error. Should that be something specific?



Below is what I cam seeing

 

[parky]

Try just uploading the plc parameters or plc parameters & program leave the device memory for now see if that works perhaps from that you can see what the memory capacity is. perhaps load each one individually I have never worked on a motion CPU so no idea what the actual problem is.

 

[parky]

Try opening GXDeveloper do not select a new project and PLC type then go on-line & try to upload everything to an unset project it might work.

 

[lbcobra]

I don't have a program to upload. I'm trying to download and preserve the existing SW of the machine.


If I do an upload I will lose the software the operates the machine.

 

[parky]

I thik this is where the confusion lies, It depends on the IDE treats upload/download.
I understand you want to take a copy of the program in the plc & save it incase you loose the program.
The problem with upload/download terminology is the following:
Upload from PLC to PC or is it upload from PC to PLC.
Turn this round & you have Download from to PLC to PC or is it Download from PC to PLC. it does get confusing a better terminology is probably
copy from PLC to PC (or file) copy from PC (file) to PLC.
What I'm suggesting is after you open up GXDeveloper do not create a new project, goto online, select read from plc then select the plc type and set the interface i.e. 232/usb/ethernet then test connection & tyr the upload.
Do not create a new project before the read from PLC because I think the problem is that by creating a blank project with the selected plc puts default plc parameters so they do not match what is in the plc, by not having any plc parameters i.e. no selected plc in the project it should upload (or download if that is your preferred way of saying plc to pc).
I cannot test it on a motion plc but it works on Q or FX.

 

[lbcobra]

Yes, moving from PLC to PC. I consider that a download since it is incoming to the PC. Sorry for not being more clear. I can give it a try on Monday.


len