| 摘要 |
PURPOSE: To perform high-accuracy A/D conversion and D/A conversion without damaging the real-time property of emulation between the emulator and an application system with different operating voltages. CONSTITUTION: A voltage comparator circuit 10a at a correcting converting circuit 10 built in a slave microcomputer 4 digitally converts an operating voltage Vcc of the emulator and an analog system operating voltage AVcc of the application system, calculates how many times the operating voltage Vcc is in comparison with the analog system operating voltage AVcc, namely, calculates a Vcc/AVcc and stores that value in a correcting value storage register 10b. An analog signal ANn to be A/D converted is converted to a digital signal by an A/D converter 9 and outputted to a level correcting circuit 10c. The level correcting circuit 10c multiplies the relevant digital value with the Vcc/AVcc stored in the correcting value storage register 10b, level conversion is performed to the digital value of the operating voltage Vcc, and it is inputted to a CPU 4b. |
