| 摘要 |
PURPOSE:To perform a RAM test in a short time by means of inexpensive configuration of hardware. CONSTITUTION:A microprocessor 1 reads the test data written in RAM 3 at the time of test and sends it to a register 11 of a RAM test circuit 4, transferring the same test data directly to a register 12. Output signals of registers 11 and 12 are compared by a comparison circuit 13, detecting the equality or inequality of the both. In the case of an inequality, a detection signal of the logic '1' is latched by a flip-flop 14 to be read out on a bus through a buffer 15. The microprocessor 1 tests the RAN 3 by fetching the detection signals on the bus. |
