| 摘要 |
PURPOSE:To prevent an overflow of a tracer memory, by writing the writing timing to the tracer memory together with the timer value when a signal to be traced varies. CONSTITUTION:When either one of signals 201-20n to be traced has a change, the values of these signals and the count value 33 of a counter circuit 11 of that moment are written to the address of a tracer memory 12 which is shown by a memory address 28. At the same time, the output 26 of an OR gate 6 clears the count value of the circuit 11 and then starts counting time until either one of the signals 201-20n corresponding to the circuits 31-3n having an indication of validity has a change. Furthermore the input 27 of a memory address register 8 is replaced, and the reading address of the memory 12 is replaced. In such a way, the writing is carried out to the memory 12 together with the hitherto time. |
