The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 15, 1996
Filed:
May. 31, 1994
Tetsu Tashiro, Itami, JP;
Yoshiki Cho, Itami, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A control circuit is provided which enables the main CPU 23 to access a memory space of the sub CPU 1 by means of the test mode control register 4 which can be controlled via the main CPU bus 10. Also a control circuit is provided to branch into a break routine by comparing the value of the program counter 5 of the sub CPU 1 and the value set in the break vector register 7. Further, a control circuit which enables it to reset the sub CPU 1, to branch according to a test vector and to make break branch under the control of the main CPU 23 is provided, thereby making it easy to incorporate the sub CPU 1 on-chip in the conventional single CPU constitution. Thus testing environment and debugging environment for the sub CPU 1 is provided in the microcomputer having a plurality of CPUs on a single chip without connecting the exclusive test terminal of the sub CPU 1 or the sub CPU bus 28 with the outside.