Chapter 5: Functional Description; Introduction; Processor Board - HP 200 Series Hardware Support Document

Functional Description
Chapter
5
Introduction
This chapter describes the function of the assemblies in the HP 981 7 computer. The functional
description may be easier to follow if you locate the various components on the block diagram,
Figure 5-3.
The HP 981 7 consists of these functional units:
• Processor board
• I/O connectorboard
• Power supply
The function of these units is as follows:
Processor Board
The processor board consists of two distinct sections, the processor section and the input/output
section.
The processor section contains the CPU, a memory management unit, a programmable timer
module, a system configuration register, a power-up configuration register, self test LEDs and
control circuitry buffers.
The CPU is a Motorola MC68010 microprocessor, with 32-bit data and address registers, 16
megabyte direct addreSSing range, 57 instruction types and memory-mapped I/O. The CPU con-
trols a bus with 23 address lines, 16 data lines and 17 control lines. Control signals allow asynchro-
nous communication with a variety of memory and I/O devices, and allow for different bus masters,
interrupt operation, and selective byte or word addreSSing.
The memory managernent unit provides virtual memory capabilities to the computer. The prog-
rammable timer module provides periodic interrupts to the CPU for multi-tasking purposes.
The systen1 configuration register is a PROM which contains information about the configuration of
the system as well as the machine serial number. The power-up configuration register is a switch
block which allows the user to define a power-up configuration for the software. The eight self-test
LEDs report the status of the self-test and any errors encountered by it.
The input/output (1/0) section of the processor board contains the boot ROM, a keyboard and
speaker interface, an HP-IB interface and an RS-232 interface.
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