| 摘要 |
A boundary scanning element comprising a plurality of boundary cells on the input terminal side respectively assigned to the input terminals and connected in series therewith, a plurality of boundary cells on the output terminal side respectively assigned to the output terminals and connected in series therewith, a TAP circuit for controlling the input and output of data to and from the boundary cells on the input terminal side and on the output terminal side, TDI terminals for receiving serial data that are to be given to the boundary cells, TDO terminals for outputting data from the boundary cells as serial data, TCK terminals for receiving clock signals, and TMS terminals for receiving a mode signal for changing over the operation mode of the TAP circuit, the boundary cells on the input terminal side and the boundary cells on the output terminal side being connected in parallel between the TDI terminals and the TDO terminals characterized by being provided with two sets each comprising the boundary cells on the input terminal side, the boundary cells on the output terminal side, the TDI terminals, the TDO terminals and the TAP circuit. |
