![Intel 8XC196NT Скачать руководство пользователя страница 348](http://html1.mh-extra.com/html/intel/8xc196nt/8xc196nt_user-manual_2072210348.webp)
14-29
INTERFACING WITH EXTERNAL MEMORY
14.7.3 Address Valid Strobe Mode
When the address valid strobe mode is selected, the device generates the address valid signal
(ADV#) instead of the address latch enable signal (ALE). ADV# is asserted after an external ad-
dress is valid (see Figure 14-16). This signal can be used to latch the valid address and simulta-
neously enable an external memory device.
Figure 14-16. Address Valid Strobe Mode
The difference between ALE and ADV# is that ADV# is asserted for the entire bus cycle, not just
to latch the address. Figure 14-17 shows the difference between ALE and ADV# for a single read
or write cycle. Note that for back-to-back bus access, the ADV# function will look identical to
the ALE function. The difference becomes apparent only when the bus is idle. Because ADV# is
high during these periods, external memory will be disabled, thus saving power.
ADV#
WR# or RD#
BHE#
AD15:0
Valid
Data Out
Address
16-bit Bus Cycle
8-bit Bus Cycle
Address High
Data Out
ADV#
WR# or RD#
AD7:0
AD15:0
Addr
Low
Extended Address
A19:16
Extended Address
A19:16
A0289-02
Содержание 8XC196NT
Страница 1: ...8XC196NT Microcontroller User s Manual...
Страница 2: ...8XC196NT Microcontroller User s Manual June 1995 Order Number 272317 003...
Страница 22: ...1 Guide to This Manual...
Страница 23: ......
Страница 35: ......
Страница 36: ...2 Architectural Overview...
Страница 37: ......
Страница 49: ......
Страница 50: ...3 Programming Considerations...
Страница 51: ......
Страница 66: ...4 Memory Partitions...
Страница 67: ......
Страница 104: ...5 Standard and PTS Interrupts...
Страница 105: ......
Страница 147: ......
Страница 148: ...6 I O Ports...
Страница 149: ......
Страница 176: ...7 Serial I O SIO Port...
Страница 177: ......
Страница 194: ...8 Synchronous Serial I O SSIO Port...
Страница 195: ......
Страница 211: ......
Страница 212: ...9 Slave Port...
Страница 213: ......
Страница 231: ......
Страница 232: ...10 Event Processor Array EPA...
Страница 233: ......
Страница 270: ...11 Analog to digital Converter...
Страница 271: ......
Страница 291: ......
Страница 292: ...12 Minimum Hardware Considerations...
Страница 293: ......
Страница 306: ...13 Special Operating Modes...
Страница 307: ......
Страница 317: ......
Страница 318: ...14 Interfacing with External Memory...
Страница 319: ......
Страница 362: ...15 Programming the Nonvolatile Memory...
Страница 363: ......
Страница 408: ...A Instruction Set Reference...
Страница 409: ......
Страница 476: ...B Signal Descriptions...
Страница 477: ......
Страница 493: ......
Страница 494: ...C Registers...
Страница 495: ......
Страница 565: ......
Страница 566: ...Glossary...
Страница 567: ......
Страница 580: ...Index...
Страница 581: ......
Страница 597: ......