183
4.17 Bus Timing
[Explanation of operation]
•
Write control is performed with only the CAS control signals (including CASL and CASH)
while RAS is lowered to "L", and then WE (including WEL and WEH) is lowered to "L".
•
Column addresses and output data are output in Q4 and Q5 cycles.
❍
CS area (CS4/CS5) switch-over in high-speed page mode, read and write combination,
2CAS/1WE
Figure 4.17-27 Example 3 of DRAM Interface Timing Chart in High-Speed Page Mode
[Explanation of operation]
•
Even if the CS area is switched, RAS remains at "L" in high-speed page mode.
•
When a bus cycle starts from a high-speed page, RDX in a read cycle goes down to "L" from
the rising edge of Q4 and is negated when the Q5 cycle ends. In a write cycle, it goes down
to "L" from the rising edge of WE (including WEL and WEH) Q4 and is negated when the Q5
cycle ends.
•
CS4X and CS5X change at the same time as the output address. When a bus cycle starts
from a high-speed page, they change from the Q4 cycle as with the column address.
Q4
CLK
A24-00
CS5X col.adr
CS5X col.adr
CS5X col.adr
CS4X col.adr
CS4X col.adr
D31-24
Write
D23-16
Read
Write
CS4X
CS5X
RDX
CS4:RAS
CS4:CASL
CS4:CASH
CS4:WE
CS5:RAS
CS5:CASL
CS5:CASH
CS5:WE
CS5 area
Q5
Q4
Q5
Q4
Q5
Q4
Q5
Q4
Q5
CS4 area
Idle
Read
Write
Write
Read
Read
Read
Read
Содержание MB91F109
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Страница 3: ...FUJITSU LIMITED FR30 32 Bit Microcontroller MB91F109 Hardware Manual ...
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Страница 10: ...vi ...
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Страница 95: ...71 2 10 Operation Mode MODR writing RSTX reset MD2 1 0 BW1 and BW0 of AMD0 to AMD5 Bus width specification ...
Страница 96: ...72 CHAPTER 2 CPU ...
Страница 224: ...200 CHAPTER 4 BUS INTERFACE ...
Страница 234: ...210 CHAPTER 5 I O PORTS ...
Страница 268: ...244 CHAPTER 9 U TIMER ...
Страница 290: ...266 CHAPTER 10 UART ...
Страница 314: ...290 CHAPTER 12 16 BIT RELOAD TIMER ...
Страница 322: ...298 CHAPTER 13 BIT SEARCH MODULE ...
Страница 392: ...368 CHAPTER 16 FLASH MEMORY ...
Страница 432: ...408 APPENDIX E Instructions F Table E 2 Instruction Formats OP rel11 5 11 ...
Страница 448: ...424 APPENDIX E Instructions ...
Страница 449: ...425 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
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