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Bus Controller (BC)
8-2
8.1
Overview
The bus controller (BC) controls interfacing between the CPU core, internal I/O (peripherals), and devices external
to the chip. The bus controller also handles arbitration between the internal and external buses. In addition, in an
interface with devices external to the chip, it is possible to select whether address pins and data pins are separate or
multiplex. The bus controller outputs four chip select signals, RAS/CAS signals, and other signals for an external
bus interface, permitting ROM, SRAM, DRAM, and other peripheral LSIs to be connected directly to this
microcontroller.
8.2
Features
The features of the bus controller are described below.
■
High-speed control of the internal and external buses through the CPU clock (MCLK) is possible.
- Synchronous mode (synchronized with IOCLK) is supported for the internal I/O bus.
Synchronousmode (synchronized with SYSCLK) and asynchronous mode (synchronized with
MCLK) are supported for the external bus.
■
External memory space can be partitioned into four blocks
- Chip select signal output for each block
- The bus width can be set to 8 or 16 bits for blocks 0 to 3
- Blocks 0 to 3 can be switched between synchronous mode and asynchronous mode
- Blocks 0 to 3 permit the read/write timing to be set through the software
- Blocks 1 and 2 can be used as DRAM space
- Blocks 2 and 3 permit use for handshaking
■
DRAM interface
- Address multiplexing function
- Permit the read/write timing to be set through the software
- Support for software page mode through software settings
- Support for CAS-before-RAS refresh (Programmable refresh cycle)
■
Permits switching between separate/multiplex address and data pins through the external input pin
settings
- Blocks 0 to 3 permit switching between separate/multiplex address and data pins through the external
input pin settings
- Using multiplex address and data pins permit the allocation of microcontroller I/O and peripheral
pins and reducing the number of external device pins
- Permits direct connection with ROM, SRAM, and DRAM without external circuitry
■
Avoids time penalty during storage operations through use of store buffer (one word)
- Support for storage in on-chip peripheral circuits and external devices
- When the store buffer is empty, storage operations are completed with no wait states, and the CPU
can execute subsequent processing
Summary of Contents for MN103001G/F01K
Page 1: ...MICROCOMPUTER MN1030 MN103001G F01K LSI User s Manual Pub No 23101 050E ...
Page 2: ......
Page 4: ......
Page 6: ......
Page 8: ......
Page 9: ...Table of Contents List of Figures and Tables 0 ...
Page 26: ...xviii ...
Page 27: ...1 0 1 General Specifications ...
Page 35: ...2 CPU 2 ...
Page 57: ...3 Extension Instruction Specifications 3 ...
Page 96: ...Extension Instruction Specifications 3 40 ...
Page 97: ...4 Memory Modes 3 4 ...
Page 102: ...Memory Modes 4 6 ...
Page 103: ...5 Operating Mode 5 ...
Page 107: ...6 Clock Generator 6 13 ...
Page 111: ...7 Internal Memory 7 ...
Page 114: ...Internal Memory 7 4 ...
Page 115: ...8 Bus Controller BC 8 ...
Page 189: ...9 Interrupt Controller 9 ...
Page 220: ...Interrupt Controller 9 32 ...
Page 221: ...10 8 bit Timers 9 10 ...
Page 254: ...8 bit Timers 10 34 ...
Page 255: ...11 16 bit Timers 11 ...
Page 292: ...16 bit Timers 11 38 ...
Page 293: ...12 Watchdog Timer 11 12 ...
Page 302: ...Watchdog Timer 12 10 ...
Page 303: ...13 Serial Interface 13 ...
Page 354: ...Serial Interface 13 52 ...
Page 355: ...14 A D Converter 14 ...
Page 367: ...15 I O Ports 15 ...
Page 431: ...16 Internal Flash Memory 16 ...
Page 439: ...17 17 Ordering Mask ROM ...
Page 442: ...Ordering Mask ROM 17 4 ...
Page 443: ...Appendix ...