Hello,
The problem asks me to make a 3-8 decoder (no enable input required), with inputs x,y,z and 8 active high outputs labelled 0-7. The only building block I can use is a 2-4 decoder with active high enable.
I didn't listen much in class, regrettably so I don't know much of the terms nor how I'm really supposed to approach this, so please help me along the way.
Right now I have two 2-4 decoders, one representing 0-3, and another representing 4-7. Input x is connected to both the decoder's active high enable. Input Y and input Z are connected in the regular inputs of the respecting decoders.
I think this is correct, but what am I missing. I was thinking, that if I didn't place a inverter before the enable on the top or bottom decoder, then the decoders won't be labelled 0-7 but rather two seperate entities. Am I correct in thinking that? Or is there a way where I can "assign" one decoder to be 0-3 without the use of an inverter?
Also, how is active high and active low represented. If a bubble is on the enable of the decoder, does that mean active high or active low? How about when the bubble is on the output of the decoder? Is that representing active high or active low?
Thank you for the assistance.
The problem asks me to make a 3-8 decoder (no enable input required), with inputs x,y,z and 8 active high outputs labelled 0-7. The only building block I can use is a 2-4 decoder with active high enable.
I didn't listen much in class, regrettably so I don't know much of the terms nor how I'm really supposed to approach this, so please help me along the way.
Right now I have two 2-4 decoders, one representing 0-3, and another representing 4-7. Input x is connected to both the decoder's active high enable. Input Y and input Z are connected in the regular inputs of the respecting decoders.
I think this is correct, but what am I missing. I was thinking, that if I didn't place a inverter before the enable on the top or bottom decoder, then the decoders won't be labelled 0-7 but rather two seperate entities. Am I correct in thinking that? Or is there a way where I can "assign" one decoder to be 0-3 without the use of an inverter?
Also, how is active high and active low represented. If a bubble is on the enable of the decoder, does that mean active high or active low? How about when the bubble is on the output of the decoder? Is that representing active high or active low?
Thank you for the assistance.