| 摘要 |
PURPOSE: To enable the bus to be released at the bus release request from the user's side by providing a control circuit receiving a user bus release request on a user actual device interface control part even at the time of a firmware program operation environment. CONSTITUTION: When a user actual device 3 makes a user actual device interface control part 4 activate a bus release request signal/UBREQ 9 when an emulator is in a firmware program operation environment, the user actual device interface control part 4 does not output the bus release request signal/ BREQ 12 on the side of an emulator to a chip 1 for evaluation and does not stop the operation of the chip 1 for evaluation. In this state, a user signal mask timing signal 16 is issued within the user actual device interface control part 4, and an address for user and a data bus 7, etc., become high impedance state. Subsequently, the response signal/UBACK 10 from the user interface control part 4 is activated and a bus release is notified to the user actual device 3. |
