1. In the GX-Develop (programming interface) menu, the “Display” drop-down – comment display, make sure all comments can be seen, then click on the “Device Comments” in the leftmost project bar, double-click “COMMENT” “All the uncommented X, Y, and M devices have been commented out. You can add them after you need to fill in the comments. You can see them by closing them back to the programming interface.” – This method is suitable for batch comments
2. On the programming interface menu bar, find the “Comment Edit” button, click on the double-click on the device you want to edit, and type it, but if you want to continue programming, you need to click this button again to return to the programming state.