| 摘要 |
PURPOSE:To obtain both functions of an in-circuit emulator and a PROM emulator with a single debugger by issuing a bus request from a control means to the in-circuit emulator to set the in-circuit emulator to the DMA state. CONSTITUTION:A control part 14 is provided with a control circuit pat for the in-circuit emulator and that for the PROM emulator, and these control circuit parts are switched to execute the peculiar control operation. When the control circuit part for the PROM emulator issues the bus request to the control circuit part for the in-circuit emulator, the control circuit part for the in-circuit emulator goes to the high impedance state to bring about the DMA state (direct memory access state). Consequently, a target system directly accesses an emulation memory 8 through a bus 16. Thus, the single debugger functions as the in-circuit emulator as well as the PROM emulator. |
