I want to use RCX to simulate TG1-TG4 in circuit above. When RCX output is 1v, TG1 is on, 3v for TG2 on, 5v for TG3 on and 7v for TG4 on, then 0v for all TGs off.
I think LM3914 can do this task, but I am a software engineer and I don't know how to design circuit, can you help me?