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Bus Controller (BC)
8-73
8.16 Cautions
These cautions concern the BC. These cautions must be heeded, since failure to do so may result in misoperation.
1.
Do not change the contents of the relevant memory control register and the DRAM control register while
accessing external memory space, except when software page mode is not in effect.
2.
Do not overwrite the refresh counter register while the REFE bit is “1” in the DRAM control register.
3.
“0” is output on pins A23* to 16 when pins ADM15 to 0 are operating as data pins in address/data multiplex
mode, as shown in the diagram below; as a result, in order to use pins A23* to 16 while pins ADM15 to 0 are
operating as data pins, it is necessary to latch the output on pins A23* to 16 with the address strobe AS.
*: A23 also serves as CS3.
Fig. 8-16-1 Example of Address Pin Usage in Address/Data Multiplex Mode
4.
When entering the stop mode, the output mode of pins ADM15 to 0 is undefined. Therefore, when pins
ADM15 to 0 are being pulled up according to the I/O port output mode register setting, the pull-up setting for
pins ADM15 to 0 should be released before entering the stop mode in order to avoid power consumption in the
stop mode due to the pull-up resistance.
Note: For details on the output mode register settings, refer to Chapter 15, “I/O Ports.”
5.
Interrupts are prohibited and the bus is locked (occupied by the CPU) when executing BSET or BCLR, however,
if a BSET or BCLR instruction is executed during program execution in external memory, a bus authority
release due to an external bus request may be interposed between the data read and data write by the BSET or
BCLR instruction.
If the atomic bus cycles (i.e. bus lock) of the BSET or BCLR instruction need to be guaranteed in a system that
uses multiple processors, either of the following measures should be taken.
1. A program in which a BSET or BCLR instruction is executed should be placed in internal memory.
Latched
AS
CSn
MCLK
SYSCLK
ADM15 to 0
ASA
ADE
A23* to 16
A23* to 16
BCS
BCE
ASN
“0” (low level)
data
addr
addr
addr
: Undefined
: A23 also serves as CS3
*
: Undefined or Hi-Z
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 ...