Ferranti F100-L CPU family

F100-L is a 16-bit microprocessor, designed by British company Ferranti Limited for military applications. Introduced in 1976, the processor operated at frequencies from DC and up to 8 MHz, and could directly address 32K words of memory, or 64 KB. The CPU instruction set was comprised of 28 basic instructions, and supported direct, pointer indirect, immediate and indirect immediate addressing modes. Depending on the instruction, its execution time could be as low as 1 microsecond, or as high as 6 microseconds, and the average instruction execution time was reported to be in the 3 - 4 microsecond range. The F100-L system could be "expanded" to handle multiply and divide by adding external chip, such as F101-L. Ferranti also manufactured or planned to manufacture the following support chips:

• F111-L Control interface and F112-L data interface units
• F113-L high-speed memory interface
• F114-L medium speed memory interface (low-power version)
• F115-L real-time interrupt unit with on-chip oscillator
• F117-L two-channel interrupt controller with on-chip oscillator
• ZN1001 clock generator

The Ferranti F100 microprocessor was produced in 40-pin ceramic DIP package.