| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To perform read-out protection of programs and data stored in a memory in the case that the memory is connected to a microprocessor with a debug interface such as a JTAG mounted thereon via a bus. <P>SOLUTION: A control part 1 (bus output part 142) outputs prescribed data to a bus (address bus 15 or data bus 16) in the case that both a connection detection signal showing that a debugger 2 is connected and an access control signal from a microprocessor 10 are effective, and data propagating in the bus is destroyed to be undefined by collision of the prescribed data with data stored in a memory (external flash ROM 12 or external RAM 13) to be output to the bus. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
