EPROM/SRAM Area
The PME 68-1B contains four sockets for 28-pin, JEDEC compatible devices. Two are
defined as the System Area and contain EPROMs holding the standard Monitor etc.
The two remaining sockets are user definable and can contain EPROM or SRAM
devices.
Access Speed Selection
To enable the user to fit a range of devices, the EPROM areas have a jumper area to al-
low access time speeds to be selected. This provides a range of access times. The
access time selected will apply to both system and user areas. Details of selection are
provided in Chapter 4.
System Area
The board contains jumpers which allow the System Area to be configured to use the
following devices:
EPROM 2732
4k x 8 bit,
8 kbytes total
EPROM 2764
8k x 8 bit,
16 kbytes total
EPROM 27128
16k x 8 bit,
32 kbytes total
EPROM 27256
32k x 8 bit,
64 kbytes total
EPROM 27512
64k x 8 bit,
128 kbytes total
The PME68/Monitor is supplied as two 2764 type EPROMs labelled 0547 and 0548. The
0547 EPROM contains the upper byte and 0548 the lower byte. These devices are
located in board positions J24 and J40 respectively. For details of PLUM contact your
supplier.
During the power-up phase the Initial Stack Pointer and Initial Program Counter are
down mapped from the System EPROMs to locations $000000 to $000003 and $000004
to $000007 respectively in the on-board RAM. They are then read from these locations
by the CPU.
The System Area may be re-configured to take 2732, 27128, 27256 or 27512 type
EPROMs. Refer to Chapter 4, for details of jumper settings required for these devices.
PME68-1B Manual
Page 16 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...