JPS55135954A - Common memory access system - Google Patents

Common memory access system

Info

Publication number
JPS55135954A
JPS55135954A JP4281579A JP4281579A JPS55135954A JP S55135954 A JPS55135954 A JP S55135954A JP 4281579 A JP4281579 A JP 4281579A JP 4281579 A JP4281579 A JP 4281579A JP S55135954 A JPS55135954 A JP S55135954A
Authority
JP
Japan
Prior art keywords
common memory
microcomputer
parts
memory part
access
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP4281579A
Other languages
Japanese (ja)
Inventor
Akihiro Baba
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP4281579A priority Critical patent/JPS55135954A/en
Publication of JPS55135954A publication Critical patent/JPS55135954A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE: To avoid the simultaneous access of the common memory part by making a microcomputer have its peculiar time limit, and also to make it possible to execute a peculiar program in case several computers access the common memory at the same time.
CONSTITUTION: In case the common memory part 104 is accessed by use of a microcomputer 101 and a microcomputer 102, the bus changeover part 103 is provided in the bus 105 by which the digital parts 111 and 121 of the respective computers 102 and 102, and the digital output parts 112 and 122 are connected, and to this changeover part 103 is connected the common memory part 104. Moreover, the respective input parts 111 and 121 and the output parts 112 and 122 are connected each other in order to mutually watch the input and output status of the respective computers 101 and 102, therefore it is possible to avoid the simultaneous access of the same program of the common memory part 104, and to start execution of a peculiar program without an access time.
COPYRIGHT: (C)1980,JPO&Japio
JP4281579A 1979-04-09 1979-04-09 Common memory access system Pending JPS55135954A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4281579A JPS55135954A (en) 1979-04-09 1979-04-09 Common memory access system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4281579A JPS55135954A (en) 1979-04-09 1979-04-09 Common memory access system

Publications (1)

Publication Number Publication Date
JPS55135954A true JPS55135954A (en) 1980-10-23

Family

ID=12646437

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4281579A Pending JPS55135954A (en) 1979-04-09 1979-04-09 Common memory access system

Country Status (1)

Country Link
JP (1) JPS55135954A (en)

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