Ep 029: Active Low Decoders

This video introduces the concept of an "active low" signal and how they're used in a simple circuit called a decoder.
Takeaways: At the completion of this lesson, each student should be able to:
• explain the concept of an "active low" signal and
• design a simple active low (and active high) decoder circuit.
#activelow #and #logic

[@stefanpapp4237]

loved the video thank you

[@Q5Grafx]

Im trying to learn CNC milling. I bought a low cost machine that could really do nothing at least without flaws because of emi and power. So i upgraded all and am now at the last part which is what brings me here. So i was getting missed steps and decided to go closed loop hybrid stepper motors. its a simple magnetic decoder for rotational value to determine actual position. anyways the active low and active high are whats confusing me. on my control board if i enable low (default) and enable low on the motor encoder i get no feedback and i can turn the motor by hand and it will stay wherever i leave it at. when i use the machine to move the axis it does but as soon as the command is over its limp for lack of any better term and i have no feedback on the oled monitors on the motors. If i enable active high on the control board (S4=0) and enable Active high on the motor encoder board i get feedback on the oled, the motor is under constant tension if i turn it it will turn right back to the start position. the manufacturer suggests leaving the motor at enable low. but it doesnt seem to work that way but i am new to this i dont really know if the motor is supposed to be under constant tension or only while running. I dont want to smoke any more motors. and there is a language barrier with the manufacturer. many things im hearing are from posts on the manufacturers github but i again feel like im trying to interpret greek. My Y axis was not moving correctly it would go for a millisecond and stop and still report it was moving but doing nothing. then it started a massive vibrating buzz unstoppable till power was cut and the motor more or less seized. i tried swapping cables. driver cards, and board interfaces and it always stayed the same ( prior to seizure) I have a new motor coming in and have found out a way in mounting the magnet which should cause less interferance with the aluminum housing of the motor, but before i turn it on again and possibly destroy more. Is it supposed to be under constant tension? they include a hand turn wheel in the kit so i cant believe it should be under constant tension. or should i have the control board enable low and the motor enable high or the opposite? i wish i took electronics 40 years ago when i was in HS.