Title:
DIGITAL SIGNAL PROCESSOR LSI
Document Type and Number:
Japanese Patent JPS63173128
Kind Code:
A
Abstract:
PURPOSE: To prevent the content of an instruction ROM from being read by another person, by opening the gate of a readout indication line for an instructure ROM by a key input.
CONSTITUTION: The gate 3 is connected to the readout indication line 2 of the instruction ROM1 in a DSP.LSI that is the LSI of a digital signal processor. The gate 3 is opened only by the key input corresponding to data from a key circuit 4, and a readout program from the ROM1 is outputted by readout indication via the gate 3, and the content from the instruction ROM is protected satisfactorily from being read by another person.
Inventors:
KOBAYASHI NOBORU
Application Number:
JP467587A
Publication Date:
July 16, 1988
Filing Date:
January 12, 1987
Export Citation:
Assignee:
FUJITSU LTD
International Classes:
G06F12/14; G06F9/06; G06F21/10; G06F21/12; G06F21/62; (IPC1-7): G06F9/06; G06F12/14
Attorney, Agent or Firm:
Sadaichi Igita