| 摘要 |
PROBLEM TO BE SOLVED: To restrict an increase of a circuit area by inputting/outputting scan data with the utilization of an existing general purpose bus (shared conductor; data bus) in a data processing system including a scan circuit. SOLUTION: In the data processing system having the data bus 40 as the shared conductor, a scan chain 60 is constituted starting from a flip flop 39 connected to the data bus. Since inputting/outputting stored data in the scan chain is carried out via the data bus, the scan circuit is realized without requiring a special input/output (scan-in, scan-out) for the scan test, and the circuit area increase associated with designing the scan circuit is restricted. Moreover, flip flop 39, 48, 50 and 53 not connected to combinational circuits realize the san circuit without being replaced by scan flip flops, so that the circuit area increase associated with designing the scan circuit is restricted. |
