| 摘要 |
PROBLEM TO BE SOLVED: To obtain a bus bridge circuit having a diagnostic processing function capable of efficiently specifying the position of a fault, an ASIC and an electronic equipment. SOLUTION: When a CPU executes writing processing in an I/O register 13 in order to execute diagnosis, a data storing register 60 traps and stores 1st data outputted from the CPU 20. When the CPU 20 continuously executes reading processing from the register 13 twice in order to execute check, the 1st data from the register 60 and 2nd data from the register 13 are continuously outputted to the CPU 20. The CPU 20 compares the write data with the 1st and 2nd data to judge which includes a fault position out of plural buses BUS1, BUS2. A write address for writing is stored and compared with a read address for reading. A flag register stores a diagnostic mode flag to be turned on at the time of reset and to be turned off at the end of diagnostic processing. |
