15
15-9
Ver.0.10
EXTERNAL BUS INTERFACE
15.2 Read/Write Operations
Figure 15.2.4 Internal Bus Access during Bus Free State
Note 1 : Hi-Z denotes a high-impedance state.
Note 2 : BCLK is not output.
(2) When Bus Mode Control Register = 1
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External read/write operations are performed using the address bus, data bus, and signals CS0,
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CS1, RD, BHE, BLE, WAIT, and WR. In external read cycle, the RD signal goes low and BHE or
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BLE output for the byte position from which to read is pulled low, reading data from only the byte
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position of the bus. In external write cycle, the WR signal goes low and BHE or BLE output for the
byte position to which to write is pulled low, writing data to the necessary byte position.
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When an external bus cycle starts, wait cycles are inserted as long as the WAIT signal is low.
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Unless the WAIT signal is needed, leave it held high. During external bus cycle, at least one wait
cycle is inserted even for the shortest-case access. (The shortest bus cycle is 2 BCLK periods.)
When not using the WAIT function, the pin can be used as P71 by setting the P7 Operation Mode
Register P71MOD bit to 0.
"
H"
"H"
Hi-z
"H"
"H"
Bus-free state
internal bus access
BCLK
A11 - A30
CS0, CS1
BHE, BLE
DB0 - DB15
WAIT
RD
WR
Содержание M32170F3VFP
Страница 19: ...CHAPTER 1 CHAPTER 1 OVERVIEW 1 1 Outline of the 32170 1 2 Block Diagram 1 3 Pin Function 1 4 Pin Layout ...
Страница 42: ...1 1 24 Ver 0 10 OVERVIEW 1 4 Pin Layout This is a blank page ...
Страница 56: ...2 2 14 Ver 0 10 This is a blank page ...
Страница 88: ...3 3 32 Ver 0 10 ADDRESS SPACE 3 7 Notes on Address Space This is a blank page ...
Страница 192: ...6 6 58 Ver 0 10 INTERNAL MEMORY 6 9 Precautions to Be Taken When Rewriting Flash Memory This is a blank page ...
Страница 270: ...9 9 40 Ver 0 10 DMAC 9 4 Precautions about the DMAC This is a blank page ...
Страница 498: ...10 10 228 Ver 0 10 MULTIJUNCTION TIMERS 10 9 TOM Output related 16 bit Timer This is a blank page ...
Страница 550: ...11 11 52 Ver 0 10 A D CONVERTERS 11 4 Precautions on Using A D Converters This is a blank page ...
Страница 614: ...12 12 64 Ver 0 10 This is a blank page SERIAL I O 12 9 Precautions on Using UART Mode ...
Страница 710: ...14 14 16 Ver 0 10 REAL TIME DEBUGGER RTD 14 4 Typical Connection with the Host This is a blank page ...
Страница 746: ...16 16 20 Ver 0 10 WAIT CONTROLLER 16 3 Typical Operation of the Wait Controller This is a blank page ...
Страница 756: ...17 17 10 Ver 0 10 RAM BACKUP MODE 17 4 Exiting RAM Backup Mode Wakeup This is a blank page ...
Страница 757: ...CHAPTER 18 CHAPTER 18 OSCILLATION CIRCUIT 18 1 Oscillator Circuit 18 2 Clock Generator Circuit ...
Страница 762: ...18 18 6 Ver 0 10 OSCILLATION CIRCUIT 18 2 Clock Generator Circuit This is a blank page ...
Страница 798: ...19 19 36 Ver 0 10 JTAG 19 6 Precautions about Board Design when Connecting JTAG This is a blank page ...
Страница 830: ...21 21 24 Ver 0 10 PRELIMINARY PRELIMINARY This is a blank page ELECTRICAL CHARACTERISTICS 21 5 AC Characteristics ...
Страница 831: ...CHAPTER 22 CHAPTER 22 TYPICAL CHARACTERISTICS 22 1 A D Conversion Characteristics ...
Страница 833: ...Appendix 1 1 Dimensional Outline Drawing APPENDIX 1 APPENDIX 1 MECHANICAL SPECIFICATIONS ...
Страница 837: ...Appendix 2 1 32170 Instruction Processing Time APPENDIX 2 APPENDIX 2 INSTRUCTION PROCESSING TIME ...
Страница 841: ...Appendix 3 1 Precautions about Noise APPENDIX 3 APPENDIX 3 PRECAUTIONS ABOUT NOISE ...