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CHAPTER 4 BUS INTERFACE
4.5
Bus Timing
This section provides detailed information on bus access operations in each of the
following modes:
• Normal bus access
• Wait cycle
• External bus request
■
Normal bus access
With a normal bus interface, a basic bus cycle contains two clock cycles for both the read and
write cycles. This manual refers to the two cycles as BA1 and BA2.
Normal bus access includes the following cycles:
•
Basic read cycle
•
Basic write cycle
•
Read cycle in each mode
•
Write cycle in each mode
•
Read/write cycle
■
Wait cycle
In the wait cycle mode, the preceding cycle is continued. The BA1 cycle is repeated until wait is
canceled.
This device has two types of wait cycles:
•
An automatic wait cycle that is set by the WTC bits in the AMD register
•
An external wait cycle that is set by the RDY pin
■
External bus request
The following two types of external bus requests are used:
•
Release of bus right
•
Acquisition of bus right
Summary of Contents for MB91150 Series
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Page 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
Page 4: ......
Page 10: ...vi ...
Page 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Page 178: ...162 CHAPTER 5 I O PORTS ...
Page 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Page 240: ...224 CHAPTER 8 PPG TIMER ...
Page 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Page 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Page 362: ...346 CHAPTER 15 UART ...
Page 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Page 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Page 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 510: ...494 INDEX ...
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