I don't doubt these are PIC based, nothing wrong with that.

That's hardly "all they are" though. One hopes that ELM is putting some software on them!

I agree that it's not hard to handle this protocol directly but this ~US$10 part saves some work. In my case I won't have a hardware UART driving this thing so outputting both 5 and 104xx (?) baud is a headache I don't want. (This will be hooked up to a serial multiplexor -- another PIC -- not the empeg.)

We need a level converter with either design.