| 摘要 |
<p>PURPOSE:To easily and accurately measure the distribution of the data volume stored in a FIFO connected to a data line. CONSTITUTION:A counter 11 counts the number of data inputted to a FIFO 2 connected to the data line and outputs a counted value 1. A counter 12 counts the number or data read out from the FIFO 2 and outputs a counted value n2. A stored data volume calculation circuit 13 subtracts the counted value n2 from the counted value n1 to output a number n3 of stored data. Each time data is inputted to the FIFO 2, a control circuit 17 accesses a storage distribution memory 14 with the number n3 of stored data as the address to read out data Da and sends it to a frequency update circuit 15 and adds one to data Da and writes the result in the same address of the storage distribution memory 14. The control circuit 17 reads out data from the storage distribution memory 14 and sends it to a display device 16 to display the distribution or the stored data volume.</p> |
