beautypg.com

Chapter 4 bus interface – FUJITSU MB91F109 FR30 User Manual

Page 12

background image

viii

3.9

Gear Function ..................................................................................................................................... 87

3.10 Standby Mode (Low Power Consumption Mechanism) ...................................................................... 90

3.10.1 Stop State ...................................................................................................................................... 92

3.10.2 Sleep State .................................................................................................................................... 95

3.10.3 Standby Mode State Transition ..................................................................................................... 98

3.11 Watchdog Function ............................................................................................................................. 99

3.12 Reset Source Hold Circuit ................................................................................................................. 101

3.13 DMA Suppression ............................................................................................................................. 103

3.14 Clock Doubler Function ..................................................................................................................... 105

3.15 Example of PLL Clock Setting .......................................................................................................... 108

CHAPTER 4

BUS INTERFACE ..................................................................................... 111

4.1

Outline of Bus Interface .................................................................................................................... 112

4.2

Chip Select Area ............................................................................................................................... 115

4.3

Bus Interface ..................................................................................................................................... 116

4.4

Area Select Register (ASR) and Area Mask Register (AMR) ........................................................... 118

4.5

Area Mode Register 0 (AMD0) .......................................................................................................... 121

4.6

Area Mode Register 1 (AMD1) .......................................................................................................... 123

4.7

Area Mode Register 32 (AMD32) ...................................................................................................... 124

4.8

Area Mode Register 4 (AMD4) .......................................................................................................... 125

4.9

Area Mode Register 5 (AMD5) .......................................................................................................... 126

4.10 DRAM Control Register 4/5 (DMCR4/5) ........................................................................................... 127

4.11 Refresh Control Register (RFCR) ..................................................................................................... 130

4.12 External Pin Control Register 0 (EPCR0) ......................................................................................... 132

4.13 External Pin Control Register 1 (EPCR1) ......................................................................................... 135

4.14 DRAM Signal Control Register (DSCR) ............................................................................................ 136

4.15 Little Endian Register (LER) ............................................................................................................. 138

4.16 Relationship between Data Bus Widths and Control Signals ........................................................... 139

4.16.1 Bus Access with Big Endians ...................................................................................................... 141

4.16.2 Bus Access with Little Endians .................................................................................................... 147

4.16.3 External Access ........................................................................................................................... 151

4.16.4 DRAM Relationships .................................................................................................................... 155

4.17 Bus Timing ........................................................................................................................................ 159

4.17.1 Basic Read Cycle ........................................................................................................................ 162

4.17.2 Basic Write Cycles ....................................................................................................................... 164

4.17.3 Read Cycles in Each Mode ......................................................................................................... 166

4.17.4 Write Cycles in Each Mode .......................................................................................................... 168

4.17.5 Read and Write Combination Cycles ........................................................................................... 170

4.17.6 Automatic Wait Cycles ................................................................................................................. 171

4.17.7 External Wait Cycles .................................................................................................................... 172

4.17.8 Usual DRAM Interface: Read ...................................................................................................... 173

4.17.9 Usual DRAM Interface: Write ....................................................................................................... 175

4.17.10 Usual DRAM Read Cycles ........................................................................................................... 177

4.17.11 Usual DRAM Write Cycles ........................................................................................................... 179

4.17.12 Automatic Wait Cycles in Usual DRAM Interface ........................................................................ 181

4.17.13 DRAM Interface in High-Speed Page Mode ................................................................................ 182

4.17.14 Single DRAM Interface: Read ...................................................................................................... 185

4.17.15 Single DRAM Interface: Write ...................................................................................................... 186

4.17.16 Single DRAM Interface ................................................................................................................ 187