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5.2.1 System Control Register (SYSCR)....................................................................... 75
5.2.2 Interrupt Priority Registers A and B (IPRA, IPRB).............................................. 76
5.2.3 IRQ Status Register (ISR)..................................................................................... 81
5.2.4 IRQ Enable Register (IER) ................................................................................... 82
5.2.5 IRQ Sense Control Register (ISCR)...................................................................... 83
5.3 Interrupt Sources ................................................................................................................ 84
5.3.1 External Interrupts................................................................................................. 84
5.3.2 Internal Interrupts.................................................................................................. 85
5.3.3 Interrupt Exception Handling Vector Table.......................................................... 85
5.4 Interrupt Operation............................................................................................................. 89
5.4.1 Interrupt Handling Process.................................................................................... 89
5.4.2 Interrupt Exception Handling Sequence ............................................................... 94
5.4.3 Interrupt Response Time....................................................................................... 95
5.5 Usage Notes........................................................................................................................ 96
5.5.1 Contention between Interrupt and Interrupt-Disabling Instruction....................... 96
5.5.2 Instructions that Inhibit Interrupts......................................................................... 97
5.5.3 Interrupts during EEPMOV Instruction Execution............................................... 97
Section 6 Bus Controller..................................................................................................... 99
6.1 Overview............................................................................................................................ 99
6.1.1 Features ................................................................................................................. 99
6.1.2 Block Diagram...................................................................................................... 100
6.1.3 Pin Configuration.................................................................................................. 101
6.1.4 Register Configuration.......................................................................................... 102
6.2 Register Descriptions.......................................................................................................... 102
6.2.1 Bus Width Control Register (ABWCR)................................................................ 102
6.2.2 Access State Control Register (ASTCR) .............................................................. 103
6.2.3 Wait Control Registers H and L (WCRH, WCRL) .............................................. 104
6.2.4 Bus Release Control Register (BRCR) ................................................................. 108
6.2.5 Bus Control Register (BCR) ................................................................................. 109
6.2.6 Chip Select Control Register (CSCR)................................................................... 111
6.2.7 Address Control Register (ADRCR)..................................................................... 112
6.3 Operation................................................................................................................................. 113
6.3.1 Area Division........................................................................................................ 113
6.3.2 Bus Specifications................................................................................................. 115
6.3.3 Memory Interfaces................................................................................................ 116
6.3.4 Chip Select Signals................................................................................................ 116
6.3.5 Address Output Method........................................................................................ 117
6.4 Basic Bus Interface............................................................................................................. 119
6.4.1 Overview............................................................................................................... 119
6.4.2 Data Size and Data Alignment.............................................................................. 119
6.4.3 Valid Strobes........................................................................................................ 120
6.4.4 Memory Areas....................................................................................................... 121