KS10 Technical Manual

This document is a preliminary and confidential technical manual (interim release) for the Digital Equipment Corporation's KS10 computer system, intended for field service training. Dated 1977-1978, it describes the KS10 as the hardware base for the low-end DECSYSTEM-2020, designed to provide mainframe software power in a mini-mid computer price range, running the TOPS20 operating system.

Key aspects covered include:

• System Configuration: The KS10 is housed in a compact cabinet containing the KS10PA (CPU, MOS memory, Unibus Adapters (UBAs), disk controller) and a BA11-K drawer for I/O peripheral controllers (e.g., communications, line printers). Memory ranges from 128K to 512K words with error correction/detection.
• Architecture: The processor is built with low-power Schottky TTL and AM2901 data path slices, featuring a virtual-address cache and general-purpose registers. It uses an internal, synchronous 36-bit backplane bus for communication between the console, CPU, memory, and I/O controllers. Bus access is arbitrated with a defined priority scheme.
• KS10 vs. KL10 Differences: The manual highlights that the KS10, unlike the KL10, does not implement public mode (operating in concealed mode only), supports only section 0 addressing (256K virtual memory), has specific interrupt handling rules, and uses a new I/O instruction set. Certain single-precision floating-point instructions are also unsupported.
• Operation and Diagnostics: An operator console with switches and indicators allows for power control, system reset, and bootstrap, as well as remote diagnosis via a KLINIK connection. The console offers both a user mode (for TOPS20 interaction) and a console mode (for direct hardware control, including memory/register examination and microcode loading). The system provides processor status words on halt for diagnostic purposes.
• Power System: Details the 861 power control and various power supplies (H7130, H765) responsible for AC distribution and component powering.

The document explicitly states that sections on installation, preventive maintenance, corrective maintenance, and some KLINIK operations are "to be supplied," indicating its preliminary and incomplete nature at the time of release.