Operational Overview
The operation of the PME 68-1B board is based around an 8 MHz or 10 MHz 68000 mi-
croprocessor unit with an asynchronous 16-bit data bus and 24-bit address bus. The
address bus provides a direct memory addressing range of 16M bytes. The CPU
communicates with on-board memory and I/O devices via an on-board local bus.
The address range from $000008 to $0FFFFF (1M byte) is assigned to on-board mem-
ory and I/O devices. All other addresses are external on the VMEbus.
The PME 68-1B board contains a number of features that allow it to act as the CPU of a
powerful system, one of a number of CPUs in a multi-processor system, or as a single
board computer.
Features
The PME 68-1B board contains the following features:
·
Motorola 68000 CPU with 8 MHz clock, variants 100 and 102 or with 10 MHz
clock, variants 101 and 103
·
Fully implemented VMEbus interface
·
128k bytes of DRAM using 64k bit devices
512k bytes DRAM using 256k bit devices. Access time 280ns. Distributed refresh
300ns every 15
m
s
·
Up to 128k bytes of EPROM for system firmware
·
Up to 64k bytes of SRAM/or 128k byte EPROM for the user
·
Real time clock with battery back-up
·
Three RS-232C serial interfaces, 110 to 38400 baud
·
Up/down load to/from a host computer (S Record format)
·
Parallel interface and 24-bit timer with 5 bit prescaler
·
Local interrupt handling via auto-interrupt vectors
·
Freely selectable address range for short I/O address accesses
·
Single level bus arbiter (Can be disabled to use an external arbiter)
·
Powerful Monitor firmware including a line by line assembler/disassembler,
register/memory manipulation routines and special I/O handling routines
·
RESET and ABORT switches
·
Transparent mode
The hardware specification of the PME 68-1B is given in Chapter 2.
PME 68-1B Manual
Page 7 Issue 5
Содержание PME 68-1B
Страница 8: ...Figure 1 The PME 68 1B Board Photograph not available in PDF PME 68 1B Manual Page 2 Issue 5...
Страница 12: ...Figure 4 Component Layout Diagram P5 P4 P3 BAT PME 68 1B Manual Page 6 Issue 5...
Страница 56: ...Figure 14 Link Areas BAT PME68 1B Manual Page 50 Issue 5...
Страница 57: ...Blank Page PME68 1B Manual Page 51 Issue 5...
Страница 59: ...Figure 15 Location of System EPROM Area 1 2 3 4 1 2 3 4 WC1 WC2 PME68 1B Manual Page 53 Issue 5...
Страница 80: ...Figure 41 Location of BERR Jumpers 1 2 3 4 WK1 WK2 BR26 2 3 1 BAT PME68 1B Manual Page 74 Issue 5...
Страница 132: ...Blank Page PME68 1B Manual Page 126 Issue 5...