search

Jakz / junk-jack-issues

Junk Jack Issues
2 stars 0 forks source link

Truth table device connects to insulated wires #29

Open ghost opened 3 years ago

ghost commented 3 years ago

In the attached screenshot, I am implementing a simple ripple counter. The right-hand truth table does not work, even though the wire to its left is insulated. If I move the truth table up one square, it operates as expected. In both cases, it is set to only assert when 0 is true. FAB5D5A9-B1A3-4E99-95FB-DB7D847D7D9E

ghost commented 3 years ago

In fact, the issue may be deeper than this. It seems that perhaps truth tables temporarily assert their inputs. In this configuration, neither truth table works. They fire at odd times or just once depending on how they are configured. If each is set as 0-active, each fires exactly once, then stops. 1BFDDD3F-B434-4AB5-BBC3-39B2E24EE3D3

ghost commented 3 years ago

Workaround: in the first configuration, the counter works as expected if the right-hand truth table is set to 0 and 1. It works equally well whether the center wire is insulated or uninsulated.

Truth tables must be used because other logic gates do not assert when don’t-care inputs are floating/disabled.