When making a single panel, the screen printing layer is usually placed on the top layer, the patch component is placed on the bottom layer, and the pads of the through-hole components will be on all layers, so the through-hole components don't have to worry about which layer to put.

In the design rules, the effective layer of wiring is set to the bottom layer (the wires at the bottom layer are blue and the wires at the top layer are red). This is a single panel.

After the layer of the patch component is set to the bottom layer, its symbols and characters default to the bottom screen printing layer, which is automatically mirrored without manual mirroring.

The PCB file of altium designer must have top layer, bottom layer and other layers. I don't see where the component end is in this software. Isn't the software you use altium designer?

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