PC15 is a circuit board designed by JKL. It has a high-performance processor, 16-bit data bus, 8-bit address bus, and integrated memory controllers. It is expandable up to 16 MiB DRAM and 4 MiB SRAM. PC15 is compatible with several operating systems, including MS-DOS, FreeDOS, and Linux. It also supports various I/O ports for connecting to peripherals, such as serial and parallel ports, as well as a USB port. Additionally, PC15 includes an RTC and BIOS that are customizable via software.