This is a brief glossary of the PA-RISC specific terminology. You can find a more detailed one at

Boot Console Handler (BCH)

This is the early boot console available during boot up on most PA-RISC machines, provided by the Processor-Dependent Code (PDC).



This a command line utility stored in the boot ROM of the PA box, which is used to configure the computer during early boot sequence. It is a part of the PA-RISC machine's firmware.

See Also: Boot Console Handler (BCH).

Guardian Service Processor (GSP)

The GSP is a console subsystem present on certain PA-RISC systems, which provides several features such as remote console, UPS management, system low level control.

High Priority Machine Check (HPMC)

Fatal system error. Processor-Dependent Code (PDC) saves machine state in the Processor Internal Memory (PIM).

Hewlett Packard Precision Architecture (HP-PA)

'HP-PA' (sometimes 'hppa') is the short way to refer to HP PA-RISC architecture. It's real meaning is: 'Hewlett Packard Precision Architecture'. It is used for instance by Debian and OpenBSD to point out their ports.

Initial Program Loader (IPL)

It is the HP standardized system bootstrap responsible for loading the operating system's kernel on PA-RISC systems. It can be launched from the BOOT_ADMIN.


Initial System Loader (ISL)

ISL is the executable that brings you into BOOT_ADMIN.

See Also: Initial Program Loader (IPL).

Logical Interchange Format (LIF)

This is a HP mass-storage format used for exchanging files among HP computer systems. It basically contains a header (identifying it as a LIF volume) and a directory of fixed size containing the files. The size of the directory is fixed when the volume is created, which explains many things about the way PALO works!


It is the name contraction of LIF image, which is indeed a file which format respects the LIF standard. It can be seen as the equivalent of an ISO file, having the LIF format instead of ISO9660.

See Also: Logical Interchange Format (LIF).

Low Priority Machine Check (LPMC)

Generally a recoverable system error.

See Also: High Priority Machine Check (HPMC).

Management Processor (MP)

The MP is a newer evolution of the GSP.

See Also: Guardian Service Processor (GSP).


PA stands for Precision Architecture. It is the name of two generations of HP processors. They are classified as PA-RISC 1.X and PA-RISC 2.0. But a system based on a PA-RISC processor is commonly called a HP-PA box.

See Also: Hewlett Packard Precision Architecture (HP-PA).

PA LOader (PALO)

PALO is the PA/Linux kernel LOader. It was designed by Paul Bame as a LILO equivalent for the PA-RISC architecture.

Processor-Dependent Code (PDC)

It is the firmware that handles all processor-dependent functionalities, including hardware initialization and self-test procedures. Once it has done this, it passes control to the ISL.

See Also: Initial System Loader (ISL).

Processor Internal Memory (PIM)

Machine state is saved here after High Priority Machine Check (HPMC), Low Priority Machine Check (LPMC), and Transfer Of Control (TOC). See PDC_PIM in "PDC Procedures" chapter of PA-RISC I/O ACD (available from

See Also: Initial System Loader (ISL).


This is not a PA-RISC specific term, though it needs explanations. Network Install, also known as netinst, are small ISOs containing everything you need to boot a computer and install it from network. They are based on the Debian distribution.


(added by special request) National Semiconductor PC87560UBD, aka SuperIO. Provides IDE, USB 1.1, Floppy Disk Controller, parallel port, 2 serial ports, UIR (Infrared), etc. But since National denies the existence of this chip and HP was the only client for this buggy PoS, the name SuckyIO has stuck.


Official term for SuckyIO.

See Also: SuckyIO.

Standard Text Interface (STI)

It defines a standardized way to access the graphic subsystem on HP-PA.

Standard Text Interface Console layer (STIcon)

It is the basic text-mode console that can run on top of any STI-capable device.

See Also: Standard Text Interface (STI).

Standard Text Interface FrameBuffer layer (STIfb)

It is a superset of STI, providing standard API to access framebuffer devices on HP-PA.

See Also: Standard Text Interface (STI).

Transfer Of Control (TOC)

This acronym can usually be found on some PA-RISC boxes, right near a tiny switch that is not often used (hopefully). On HP/UX it would make a crash dump and reset the box. It can also be requested from the Guardian Service Processor (GSP). On Linux, it will save the registers and reset, saved registers will be accessible in the Processor-Dependent Code (PDC).