AboutDave Nyce Expertise I have been an electronics engineer for 25 years. I can answer questions on analog and digital circuits and my specialty is sensors.
Experience I am the inventor on 23 US patents, and also some foreign ones. Developed sensors for over 25 years. Licensed private pilot (airplane and rotorcraft), have HAM radio license. I'm not an expert in computer networking.
Question I'm putting a computer into an old stereo receiver/amplifier that quit amplifying a while back. The display still works and I'd like to use it with the computer if it's at all possible. I'm a talented programmer and have a couple years of electornics from high school and a lot of patience. The display has a 38pin interface probably twice that many LEDs for the alphanumeric characters and various indicators. The majority of those pins run to a 64pin IC as do a fair number of push button momentary switches and 3 ribbon cables. 1 ribbon cable goes off to the am/fm board the other two go to the mainboard. The system is still operation minus the amplification. I might be able to get access to an oscilloscope. Is there any chance I might be able to reverse engineer the operation of the display or is it lost cause?
Answer Sorry I couldn't answer yesterday, the system kept saying that the site was busy.
You have two possibilities: work directly with the LEDs, or work with the installed driver IC. To work directly with the LEDs, you can identify the polarity and connections for each LED segment by probing with two leads. The two leads will come from a 9V batrtery with a series resistor of 500 ohms, 1/4 watt. When you have found the right connections for a particular LED or LED segment, it will light. Write these down until you have found all of them. Write your software to drive a hardware output that supplies about 15 mA to light each LED.
To work with the installed driver IC, the only way is to identify the IC and find the connection diagram from the IC manufacturer. nfortunately, most ICs installed in consumer electronics are proprietary and you can not find this information, but maybe you'll get lucky.
