Erased sd card by accident somehow.

I think I need the bin file to make it work again. I have an Ender 3 pro. Can anyone offer me some advice on this matter?

It seems ok I just put some gcode on it an clicked on new sd card and I think it’s going to print. Yes it has started.

Yes. The firmware is burned into the controller card. It is not needed on the SD card.

Well it is definitely printing what I put on it so all is well.

The .bin file is the firmware your printer is still using. After flashing the firmware it stays on SD card, so you can backup it. This works as the board only flash the .bin file with the latest date stamp.

So the next time you update your printer and something fails you can use that file to fix your printer. So you managed to kill your “backup”.

SKR boards use a different approach. They rename their last flashed file to “firmware.cur”, which is quite handy.

I almost understand you, pretend that you are trying to explain to a complete idiot and you won’t be far off.

Ender 3 printers cannot update firmware from files on SD card. They have to be flashed over the USB connection. It’s the same for my Ender 5. I gather that the new Ender 3 v2 can update from the SD card, but not the one @roon4660 has.

So how could I remedy this?

I wouldn’t worry about it. The odds of your printer losing its firmware are very low. If it does happen, you can just download the latest release using your computer. Bear in mind, you will have to use something like the Arduino IDE to burn the firmware to the controller.

There is no need to. The next time you flash your firmware, that binary (.bin file) will become your future backup.

Just make sure the next firmware update does not fail. If it does you need a working copy from another ender3 user.

It is like a spare door key. You keep it safe to get back in, when you are locked out and when the door lock gets replaced you replace the spare key as well.