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Section 6 Bus Controller ................................................................................ 133
6.1 Overview ......................................................................................................................... 133
6.1.1 Features .............................................................................................................. 133
6.1.2 Block Diagram ................................................................................................... 134
6.1.3 Pin Configuration ............................................................................................... 135
6.1.4 Register Configuration........................................................................................ 135
6.2 Register Descriptions ....................................................................................................... 136
6.2.1 Bus Control Register (BCR) ............................................................................... 136
6.2.2 Wait State Control Register (WSCR) .................................................................. 137
6.3 Overview of Bus Control ................................................................................................. 139
6.3.1 Bus Specifications .............................................................................................. 139
6.3.2 Advanced Mode.................................................................................................. 140
6.3.3 Normal Mode ..................................................................................................... 141
6.3.4 I/O Select Signal................................................................................................. 141
6.4 Basic Bus Interface .......................................................................................................... 142
6.4.1 Overview ............................................................................................................ 142
6.4.2 Data Size and Data Alignment ............................................................................ 142
6.4.3 Valid Strobes ...................................................................................................... 144
6.4.4 Basic Timing ...................................................................................................... 145
6.4.5 Wait Control....................................................................................................... 147
6.5 Burst ROM Interface........................................................................................................ 149
6.5.1 Overview ............................................................................................................ 149
6.5.2 Basic Timing ...................................................................................................... 149
6.5.3 Wait Control....................................................................................................... 151
6.6 Idle Cycle ........................................................................................................................ 151
6.6.1 Operation............................................................................................................ 151
6.6.2 Pin States in Idle Cycle....................................................................................... 152
6.7 Bus Arbitration ................................................................................................................ 152
6.7.1 Overview ............................................................................................................ 152
6.7.2 Operation............................................................................................................ 152
6.7.3 Bus Transfer Timing........................................................................................... 153
Section 7 Data Transfer Controller [H8S/2138 Series] ................................... 155
7.1 Overview ......................................................................................................................... 155
7.1.1 Features .............................................................................................................. 155
7.1.2 Block Diagram ................................................................................................... 156
7.1.3 Register Configuration........................................................................................ 157
7.2 Register Descriptions ....................................................................................................... 158
7.2.1 DTC Mode Register A (MRA)............................................................................ 158
7.2.2 DTC Mode Register B (MRB) ............................................................................ 160
7.2.3 DTC Source Address Register (SAR).................................................................. 161
7.2.4 DTC Destination Address Register (DAR) .......................................................... 161