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I'm working on a circuit that includes an MCP23018 I/O Expander. Here's a photo of the IC:

As you can see the pins aren't labeled. You have to figure out which end is which by looking at the little half-circle cutout on one end.

I'd like to be able to add a corresponding half-circle in my custom symbol. Or, barring that, I'd like some way to indicate which end is the half-circle end.

All DIP (dual in-line package IC chips) are assumed to be the same as far as pins are concerned. For example, lets use a 8 pin dip chip. Put the dimple on the left and start counting at the bottom left counter clockwise around to the top row. Numbers are: right to left: 1,2,3,4, then right to left on top: 5,6,7,8.

Read a few magazines about electronics, you can pick up a lot there.

If you look for DATA SHEETS online, you will see what I refer to. Good luck.

Thanks for that suggestion, Russ. I don't think it's what I need, though. I'm labeling the pins by name (VSS, VDD, etc.), not numbers. I'm also hoping this schematic can be used by amateurs who may not know that convention.