# What is this NOR feedback loop in the AGC Cross Point Generator II?

This feedback loop looks similar to a LFSR, however there are no registers present. It looks to be some kind of oscillator.

There seem to be three inputs to this component, IXP10 (pin 111), STBE (pin 237) and STBF (pin 239). There is also a tap, CGMC (pin 240).

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• Why not use a simulator and get the operation from that? – Andy aka Dec 10 '18 at 9:36
• I've done that. On a falling edge on 40240/43 (The three input NOR) a short pulse (High) outputs on CGMC. I leave to others to find out exactly what that means. I don't have the knowledge in how the inputs are generated to find it out. @tofro 's answer below might help. – UncleBod Dec 10 '18 at 13:11