參數資料
型號: M3800
廠商: Mitsubishi Electric Corporation
英文描述: Single Chip 8 Bit Microcomputer(8位單片機)
中文描述: 單芯片8位單片機(8位單片機)
文件頁數: 123/173頁
文件大?。?/td> 4203K
代理商: M3800
3800 GROUP USER’S MANUAL
3-21
APPENDIX
3.3 Notes on use
3.3.5 Notes on memory expansion mode and microprocessor mode
(1) Writing data to the port latch of port P3
In the memory expansion or the microprocessor mode, ports P3
0
and P3
1
can be used as the output port. Use the
LDM
or
STA
instruction for writing data to the port latch (address 0006
16
) of port P3.
When using a read-modify-write instruction (the
SEB
or the
CLB
instruction), allocate the read and the write
enabled memory at address 0006
16
.
Reason
In the memory expansion or microprocessor mode, address 0006
16
is allocated in the external area.
Accordingly,
Data is read from the external memory.
Data is written to both the port latch of the port P3 and the external memory.
Accordingly, when executing a read-modify-write instruction for address 0006
16
, external memory data is read and
modified, and the result is written in both the port latch of the port P3 and the external memory. If the read enabled
memory is not allocated at address 0006
16
, the read data is undefined. The undefined data is modified and written
to the port latch of the port P3. The port latch data of port P3 becomes “undefined.”
(2) Overlap of an internal memory and an external memory
When the internal and the external memory are overlapped in the memory expansion mode, the internal memory
is valid in this overlapped area. When the CPU writes or reads to this area, the following is performed :
When reading data
Only the data in the internal memory is read into the CPU and the data in the external memory is not read into
the CPU. However, as the read signal and address are still valid, the external memory data of the
corresponding address is output to the external data bus.
When writing data
Data is written in both the internal and the external memory.
相關PDF資料
PDF描述
M38000E4-XXXSP 1 watt dc-dc converters
M38000E4-XXXSS 1 watt dc-dc converters
M38000M1-XXXFP 1 watt dc-dc converters
M38000M1-XXXFS 1 watt dc-dc converters
M38000M1-XXXSP 1 watt dc-dc converters
相關代理商/技術參數
參數描述
M3800 BK001 制造商:Alpha Wire Company 功能描述:CBL 2COND 18AWG BLK 1000'
M3800 BK002 制造商:Alpha Wire Company 功能描述:CBL 2COND 18AWG BLK 500'
M3800 BK005 制造商:Alpha Wire Company 功能描述:CBL 2COND 18AWG BLK 100'
M38000E1-DXXXFP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:8-BIT SINGLE-CHIP MICROCOMPUTER 740 FAMILY / 38000 SERIES
M38000E1-DXXXSP 制造商:RENESAS 制造商全稱:Renesas Technology Corp 功能描述:8-BIT SINGLE-CHIP MICROCOMPUTER 740 FAMILY / 38000 SERIES