| 摘要 |
PURPOSE:To enable fast reading to and fast writing from scan registers circuit by setting an initial value in a memory, loading it in an LSI part, and saving the contents of the scan registers in the memory. CONSTITUTION:A scan controller (SC)30 supplies a memory address latched in the internal register to the memory 10 and initial values are written in respec tive addresses of the memory 10 corresponding to respective scan registers(SR). Then the SC 30 outputs the number of the SR as a memory address to read the contents of the memory 10 and loads data for initialization in the SRs of the LSI part. When the SRs are read, the SC 30 supplies (number of SRs plus 1) as a memory address to the memory 10 to read out the internal states of the SRs and save them in the memory 10. Consequently, the fast read from the SRs and the fast write to the SRs become possible. |
