| Область | Диапазон адресов | Разряды адреса | |||||||||||||||
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | ||
| 10 | 4800h-4FFFh | 0 | 1 | 0 | 0 | 1 | X | X | X | X | X | X | X | X | X | X | X |
| B400h-B7FFh | 1 | 0 | 1 | 1 | 0 | 1 | X | X | X | X | X | X | X | X | X | X | |
| EA00h-EBFFh | 1 | 1 | 1 | 0 | 1 | 0 | 1 | X | X | X | X | X | X | X | X | X | |
| FD20h-FD3Fh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | X | X | X | X | X | |
| FED0h-FEDFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | X | X | X | X | |
| FFA8h-FFAFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | X | X | X | |
| 11 | 5000h-57FFh | 0 | 1 | 0 | 1 | 1 | X | X | X | X | X | X | X | X | X | X | X |
| B800h-BBFFh | 1 | 0 | 1 | 1 | 1 | 0 | X | X | X | X | X | X | X | X | X | X | |
| EC00h-EDFFh | 1 | 1 | 1 | 0 | 1 | 1 | 0 | X | X | X | X | X | X | X | X | X | |
| FD40h-FD5Fh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | X | X | X | X | X | |
| FEE0h-FEEFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | X | X | X | X | |
| FFB0h-FFB7h | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | X | X | X | |
| 12 | 5800h-5FFFh | 0 | 1 | 0 | 1 | 0 | X | X | X | X | X | X | X | X | X | X | X |
| BC00h-BFFFh | 1 | 0 | 1 | 1 | 1 | 1 | X | X | X | X | X | X | X | X | X | X | |
| EE00h-EFFFh | 1 | 1 | 1 | 0 | 1 | 1 | 1 | X | X | X | X | X | X | X | X | X | |
| FD60h-FD7Fh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | X | X | X | X | X | |
| FEF0h-FEFFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | X | X | X | X | |
| FFB8h-FFBFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | X | X | X | |
| 13 | 6000h-67FFh | 0 | 1 | 1 | 0 | 1 | X | X | X | X | X | X | X | X | X | X | X |
| C000h-C3FFh | 1 | 1 | 0 | 0 | 0 | 0 | X | X | X | X | X | X | X | X | X | X | |
| F000h-F1FFh | 1 | 1 | 1 | 1 | 0 | 0 | 0 | X | X | X | X | X | X | X | X | X | |
| FD80h-FD9Fh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 0 | X | X | X | X | X | |
| FF00h-FFOFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | X | X | X | X | |
| FFC0h-FFC7h | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | X | X | X | |
| 14 | 6800h-6FFFh | 0 | 1 | 1 | 0 | 0 | X | X | X | X | X | X | X | X | X | X | X |
| C400h-C7FFh | 1 | 1 | 0 | 0 | 0 | 1 | X | X | X | X | X | X | X | X | X | X | |
| F200h-F3FFh | 1 | 1 | 1 | 1 | 0 | 0 | 1 | X | X | X | X | X | X | X | X | X | |
| FDA0h-FDBFh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | X | X | X | X | X | |
| FF10h-FF1Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | X | X | X | X | |
| FFC8h-FFCFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | X | X | X | |
| 15 | 7000h-77FFh | 0 | 1 | 1 | 1 | 1 | X | X | X | X | X | X | X | X | X | X | X |
| C800h-CBFFh | 1 | 1 | 0 | 0 | 1 | 0 | X | X | X | X | X | X | X | X | X | X | |
| F400h-F5FFh | 1 | 1 | 1 | 1 | 0 | 1 | 0 | X | X | X | X | X | X | X | X | X | |
| FDC0h-FDDFh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 0 | X | X | X | X | X | |
| FF20h-FF2Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | X | X | X | X | |
| FFD0h-FFD7h | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | X | X | X | |
| 16 | 7800h-7FFFh | 0 | 1 | 1 | 1 | 0 | X | X | X | X | X | X | X | X | X | X | X |
| CC00h-CFFFh | 1 | 1 | 0 | 0 | 1 | 1 | X | X | X | X | X | X | X | X | X | X | |
| F600h-F7FFh | 1 | 1 | 1 | 1 | 0 | 1 | 1 | X | X | X | X | X | X | X | X | X | |
| FDE0h-FDFFh | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | X | X | X | X | X | |
| FF30h-FF3Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | X | X | X | X | |
| FFD8h-FFDFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | X | X | X | X | |
| 17 | 8000h-87FFh | 1 | 0 | 0 | 0 | 1 | X | X | X | X | X | X | X | X | X | X | X |
| D000h-D3FFh | 1 | 1 | 0 | 1 | 0 | 0 | X | X | X | X | X | X | X | X | X | X | |
| F800h-F9FFh | 1 | 1 | 1 | 1 | 1 | 0 | 0 | X | X | X | X | X | X | X | X | X | |
| FE00h-FE1Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | X | X | X | X | X | |
| FF40h-FF4Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 0 | X | X | X | X | |
| FFE0h-FFE7h | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | X | X | X | X | |
| 18 | 8800h-8FFFh | 1 | 0 | 0 | 0 | 0 | X | X | X | X | X | X | X | X | X | X | X |
| D400h-D7FFh | 1 | 1 | 0 | 1 | 0 | 1 | X | X | X | X | X | X | X | X | X | X | |
| FA00h-EBFFh | 1 | 1 | 1 | 1 | 1 | 0 | 1 | X | X | X | X | X | X | X | X | X | |
| FE20h-FE3Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 1 | X | X | X | X | X | |
| FF50h-FF5Fh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | X | X | X | X | |
| FFE8h-FFEFh | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | X | X | X | X | |
В результате получена таблица прошивки ПЛМ для разделения адресного пространства 64 кБ на 18 несплошных равных частей.
Исходя из требуемого количества произведений ( 18 * 6 = 108 ) и количества выходных функций (18), выбираем в качестве элементной базы выпускаемую фирмой ADVANCEDMICRODEVICES микросхему ПЛМ PLS30S16. Эта микросхема позволяет за счет мультиплексирования четырех адресных входов с выходами иметь от 12 до 17 входов и от 8 до 12 выходов при количестве произведений до 64.
Для решения поставленной задачи берем две ПЛМ, запараллеленные входы которых подключены к шине адреса, а выходы – к входам выбора кристалла соответствующих микросхем.
Технические данные на ПЛМ PLS30S16 фирмы AMD :
- IC MASTER/Windows -
(Title) :PLD|BIP||OTPRC
Section :PROGRAMMABLE LOGIC DEVICES
CAT0 :PLD
Category :Bipolar
CAT1 :BIP
MinorA :One-Time
Programmable~Registered/Combinatorial Outputs
CAT3 :OTPRC
MDD Code :AMD
Manufacturer's Name:ADVANCED MICRO DEVICES
Device Number :PLS30S16-40
Disc :*93
Date :10/26/92
Oper :BAC
Transcode :E
RBASE :30S16
MBase :PLS30S16
Data Book :DATASHEET
Propagation Delay (:40
Maximum Clock (MHz):22.2
Product Terms :64
Flip-Flops :12
Dedicated Inputs :12-17
Bidirectional I/Os :8-12
Standby Current (mA:225
Active Current (mA):225
Pins :28
Has Image :N