Microcomputer with software protection

Details Microcomputer with software protection Microcomputer with software protection

1985-01-25

1989-04-18

Shaw, Gareth D.

Boots, shoes, and leggings

3649187, 3649498, 364969, 3649694, G06F 1300

Patent

active

048233080

ABSTRACT:
In order to protect key parts of computer programs, the instructions making up those parts are held in an EPROM forming part of a single chip microcomputer. The EPROM is connected to instruction registers by way of an instruction bus. Data used by instructions held in these registers is transferred along a data bus which is separate from the instruction bus and serves a RAM, an ALU and an input/output port. Since the status of the input/output port is ultimately controlled by the instructions and there is no connection between the instruction bus and the data bus the instructions cannot be read either directly or indirectly from the microcomputer.

REFERENCES:
patent: 3284776 (1966-11-01), Freedman
patent: 3328768 (1967-06-01), Amdahl et al.
patent: 3377624 (1968-04-01), Nelson et al.
patent: 3858182 (1974-12-01), Delagi et al.
patent: 4047244 (1977-09-01), Finkemeyer et al.
patent: 4075692 (1978-02-01), Sorensen et al.
patent: 4087856 (1978-05-01), Attanasio
patent: 4124891 (1978-11-01), Weller, III et al.
patent: 4181938 (1980-01-01), Suzuki et al.
patent: 4183085 (1980-01-01), Roberts et al.
patent: 4274138 (1981-06-01), Shimokawa
patent: 4514805 (1985-04-01), McDonough et al.

Affiliated with

Also associated with

Rating

Microcomputer with software protection does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Microcomputer with software protection, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Microcomputer with software protection will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2400478