Posted 18 Nov 2014 Dear All, I have PLC FX3u. I already made communication with it and upload the program. I made changes and want to download but there is error message : "writing during PLC ROM operation was attempted.the PLC cannot write during a ROM operation. <ES:0180201e>. 1- when I opened the black cover to make ROM switch OFF I didn't find ROM. where can I find It? 2- Assume I find this switch and make it off then download,will this program downloaded to the ROM or the PLC memory? Share this post Link to post Share on other sites
Posted 19 Nov 2014 That usually means the PLC has an EEPROM installed with the write protect switch on. Share this post Link to post Share on other sites
Posted 20 Nov 2014 Downloading to an FX with a memory card installed ALWAYS downloads to the card. The PLC always runs from the card when powered up with a card installed as well. If no memory card is installed at power on, download and operation are both from the internal memory, Do not remove the card while powered. This information is in the manuals. Share this post Link to post Share on other sites
Posted 21 Nov 2014 Thanks for replay. But now i opened the black cover and didn't find any memory. and when i make download the message which i mentioned before appears. Share this post Link to post Share on other sites
Posted 22 Nov 2014 Then I have no idea what the problem is. That error usually means a ROM is installed and write protected. Share this post Link to post Share on other sites