Bugs with USB RS232?

[Kiwi Nate 0]

HI My post virginity is now gone! I haven't been programming for long. My query is that when I am carrying out on line edits, I write changes to the PLC after pressing F4 bla bla bla and everything appears fine. I then save the newly edited program over the top of the older previous program on my hard drive and leave. Upon re-connection, wether minutes or weeks later, and again, going for an on line edit, I compare the programs and they on occasions don't match??? I have gone into IL view and have found some NOP's. I certaintly didn't put them there! Usually I am having to clear PLC memory and re write to PLC again. It did it to me again today, so to prove the point I carryed out a on line edit, saved to disk, disconnected, then re connected, opened newly saved file, online edit, compare...Bang didn't match! Crazy I am using GX Developer V8.05 (I think, low 8's any how) and supposed quality USB to RS232 converter (works on AB, Hakko screens and my SPLat boards to date) Namely the PLC's in questions are FX -1N. My boss has never heard of it before, but he has a serial port. Any thoughts? Cheers, Nathan

[Goody 5]

1, I am sure its not your cable - if you are downloading and uploading ok, then the cable is fine 2, Try to give your new edits a new unique save version number ie 'my-program V1'. I always do this - as if you find you have done something wrong - you can quickly get back to the last good version. And most importantly, in this case - you can be sure you are running the last version you saved. 3, NOP's are No-operation and get placed in the program each time you alter it. My suspicion would be you are saving and loading the program to and from two different places. Try adding version numbers and you might find that to be the case.

[Kiwi Nate 0]

Cool thanks for the reply. My folders are highly orgasnised and I only have 1 instance of every program I have worked with, so I doubt I have different saves (un-labled versions) of the same machine in different folder locations. Unless there is some stupid temporary area that they go that is invisible on the screen, you know those ~1 you see sometimes. I will put it down to an unknown anomoly for now

[Crossbow 295]

The only USB to Serial adapter Mitsubishi recommends is from Keyspan, the USA-19. Or you can buy the Mitsubishi USB to FX programming cable, part number FX-USB-AW.

[Kiwi Nate 0]

Ford recommends their genuine tow bar too. But cheers anyway.

[mitsibushiman 0]

Sorry to say this mate, but I've had no end of problems with USB to serial converter cables with many brands! Quicker and easier to just get a USB programming cable, it's one less thing to worry about IMHO!. Either that or a laptop with a serial port (I recommend my Dell ATG) Not the greatest but does the job I want for the price!)

[Crossbow 295]

Belkin, IOGear, and Targus all use pretty much the same chipset, and it doesn't tend to work well with most automation equipment, as I have proven with many vendors equipment at an integrator years ago. The Keyspan always works with the Mitsubishi stuff. That's not Mitsubishi pushing their own towbar, but a recommend publicly available solution. Although I must say I like the fact that pretty much every current product in the Mitsu line has either USB built in or a USB adapter.

[Kiwi Nate 0]

Sure, i agree. I'm not a fan of using mine either. Its from Dontronics in Australia. recommended to me by our resident software engineer (grain of salt) Hey it works uploading and downloading every time a coconut across many different brands and cables. Also, now that I have two, talking to my Hakko screen and Mitsu PLC simultaneously during commisioning is a massive plus. Is it something to do with the way it stacks the data? I use a port monitor on the specialist of circumstances to gain access to protected PLC's and boy, does some data get transferred! Guess it only takes one bad bit to go pear shaped.