| 摘要 |
PURPOSE:To generate test patterns of many channels with the aid of a memory of small capacity by compressing and storing the test patterns of the plural channels and using a method which restores the compressed pattern to the test pattern based on common control data. CONSTITUTION:For example, the test patterns Pt of the plural channels Ch having many cycles which are represented by three bits shown by a graphic are compressed by the specified method and the compressed Pt are produced. Simultaneously, the control data A0 and B0 which is common to the compressed Pt of the plural Ch is produced and respectively written in the addresses 0 - 5 of a Pt memory and a memory for controlling. Next, when it is restored to the test Pt, the Pt data of the cycles 1 - 6 of the compressed Pt is read out from the addresses 0 - 5 of the Pt memory and restored to the test Pt based on the data A0 and B0 read out from the corresponding memory for controlling. By such a method, the long and heavy test Pt extending over many channels Ch can be generated even in the case that the Pt memory of identical capacity as a whole is used. As the result, a device is made inexpensive. |
