I think it is justifiable to translate one serial protocol to another if the external data sink doesn't use the same protocol as the data source. Whether a second MCU is warranted, well, it takes a lot of pins (at least 10) ...

In this case, I want 7-bit ASCII output in parallel, strobed, data format. It only requires that one substitute a 5-6 line routine for a 25 line one that talks to the I2C hardware. It seems to me that a little 20-pin part could handle this just fine, or, for that matter, a 16-pin part.

A 68HC705 can do it in fewer than 1000 bytes, of which just under 300 are lookup tables. Unfortunately, those are not readily available any longer, and I want to send the necessary circuit diagrams and code to someone in Europe, and he needs to be able to get the part and program it there. These are ISP OTP's if you buy them that way. If I could find the MOTOROLA part here, I'd buy it here and program it and send it there. It's got to be a DIP, though.

RE