The TRS-80 MC-10 microcomputer is a lesser-known member of the TRS-80 line of home computers, produced by Tandy Corporation in the early 1980s and sold through their RadioShack chain of electronics stores.

About the size of a hardcover book, the MC-10 has four kilobytes of RAM, a Motorola MC6803 eight-bit microprocessor, a built-in serial port, and graphics capabilities similar to those of the original Color Computer (provided by the same MC6847 video display generator).

Disk drives, full-travel keyboards, medium-resolution graphics, and complete 64-kilobyte memory banks were becoming popular features for home computers; the MC-10 offered none of these, severely limiting the functions it could perform and the range of users to whom it could appeal.

Although the memory expansion interface connected directly to the CPU bus and could have been used for many applications, the edge connector involved had an unusual number of pins and was difficult to obtain.

As a result, programs have to shift bits individually into and out of the RS-232C interface, a mode of operation that entails atypical and especially critical timing requirements.