I want to use a shift register in PISO configuration to test the continuity of an external device. When there's nothing connected there will be a pull-up resistor pulling the Input HIGH and when the device is connected there will be close to no resistance, so thinking of lighting up a diode with a limiting resistor as an extra indicator. Pulling the input LOW. My question to you are which registers are suitable for this application? Feel free to come with a different solution to my problem if there is a simpler way to do it.
-Thomas