>I've been thinking about interfacing a PIC to my car's ISO 9141 bus.

Are you sure it is not a CAN BUS?

>ISO 9141 functions very similar to a three line RS-232 serial port,
>at about 10400 baud.  Is there a PIC with an onboard UART that can
>handle that data rate?  I've read in other places that the maximum
>rate is about 1200 baud, (when the clock is at 4MHz) which seems
>outrageously slow to me.  If I can't use an onboard UART, I guess
>I'll try to use a 16550 external UART to get an appropriate data
>rate.

Well I am using a 16F876 at 19.2k with a 3.6864MHz crystal, and using Fr
MacGhee's routines as interrupt driven send and receive routines it works
perfectly.

>BTW, are there any PICs with 2 onboard UARTS, for RS-232?
>I didn't find any on Microchip's web.

I believe some of the 17 and/or 18 series have 2 uarts.

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