C Parallel Interface

The Capital Software C-Interface (1985) is a third-party printer interface that let the Coleco ADAM print to standard dot-matrix printers via either the Commodore Serial Bus or Centronics Parallel. Designed by Thomas J. Golab, a one-man operation in St. Louis, Missouri, it is among the rarest documented ADAM peripherals. Installs in expansion slot #1.

The card uses five standard TTL ICs (7406, 74LS32, 74LS175, 74LS368, 74LS30) with no dedicated protocol chip — all printer protocols are bit-banged in Z80 software through the CDRIVER binary. A 6-pin DIN cable routes through a user-drilled hole in the expansion cover to the printer, or to an MW-302C Centronics adapter.