Has anyone seen anything like this?

I have a piece of code that initialises the UART, and sends out a character,
and this code is based around Fr MacGhee's picuart.asm. This seems to
initialise the UART successfully, and send the character OK, as I can see
the character on a dumb terminal attached to the hardware.

The code then goes on to initialise the I2C hardware, which is written
around the Microchip app note for I2C master mode, but when an attempt is
made to send characters on this, they come out the uart TX pin!!! This has
had me scrambling around for a while checking for places in my code
accessing the uart instead of the SSP.

The chip concerned is an SM 16F876, and I have had a look around for short
circuits, which seem to be non existant. An oscilloscope shows clocking on
the SCL line, no activity on the SDA line, which is high, and activity on
the TX line, so I do not think there is a short anywhere.

Just before I rip into changing the sm chip, I was wondering if anyone has
seen this sort of oddball behaviour, which definitely seems to point to dud
hardware.

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