Paul Rickards on Twitter: "The 556 timer IC is the basis for the long board #c64 reset circuit (along with a capacitor that checked out ok). I removed the old 556 and
NE556 Dual timer Datasheet pinout and example circuits | ElecCircuit.com | Circuit diagram, Electronic circuit projects, Circuit
555 Timers | 556 Timers | 7555 Timers Basics, Features and Application
Dual Time Delay Relays Using 556 IC
555 - 556 dual timer circuit not clear to me - Electrical Engineering Stack Exchange