The 6502 was used as the Intelligent high speed datacom controller in the Four Phase Systems minicomputers as a single board computer. Due to the nature of programming at that time, we too had to become familiar with "programmable" peripherals like this one -- Yes those were the days, Assembler, COBOL, JCL on the mini itself, and then smart disk controller, and smart datacom controllers.
We learned a lot, didn't we?