| 摘要 |
PURPOSE:To eliminate the need for unnecessarily providing a terminal in order to set a test mode by inputting a signal pattern, which is set in advance, as an initializing signal at the time of the initialization of an LSI. CONSTITUTION:When a RESET signal 101 is inputted, an internal REST signal 102 goes to be '1' and the LSI is initialized. Then, an FF305, which generates a MODE signal 103 to designate the test mode of the LSI, is also initialized. After that, when the pattern of 010 is inputted to the signal 101 after >=3 clocks pass, the FF305 is set and the signal 103 goes to be '1'. After that, when the signal 101 goes to be '0' after the >=3 clocks pass, the signal 102 also goes to be '0' after the three clocks and the initialization of the LSI is completed. Then, since the signal 103 is '1', the LSI operates as the test mode. Accordingly, the LSI is initialized and simultaneously, the test mode is, set. Thus, it is not necessary to unnecessarily provide the terminal in order to set the test mode. |
