Patent ID: 8015465
Filing Date: 2011-09-06
Classification: G01R

Abstract:
1. A scan control method of a circuit device, connected with a bus, having a test access port controller, the method comprising: setting information indicating one scan mode of a broadcast mode, a parallel mode, and a normal mode in a register unit; and cutting an output of scan out data to the test access port controller and an input of scan in data from a data register unit based on the information set in the register unit and controlling a connection between a scan register unit and the data register unit, wherein each of the data register unit and the scan register unit includes data registers for the same number of chains to be scanned at the same time, data set in one data register of the data register unit is kept in all the data registers of the scan register unit in parallel and scanned in all the scan chains in a scan in of the broadcast mode at a time of controlling the scan register unit and the data register unit, and the data set in the data register of the data register unit is kept in the data register corresponding to the scan register unit and scanned in the corresponding scan chain, in a scan in of the parallel mode.