If you need to quickly add numbers from 0 to 15, and you know how to rapidly convert to binary and back to decimal, this is for you...But if your human then this is just a fun project!! I'm going to show you how to make a 4 bit (0-15) adding calculator using 74xx series IC chips.
The chips that I used are the very basic gates like OR, AND, XOR, NOR, NAND, etc. No actual adding chips are used so its one level up from transistors, and it's totally TLL!**
By the way, this is another addition to the unofficial "Macroelectronics" catagory for all of you who have seen my diy ram instructables!
**If you use the 74hc series or 74hct series, then its technically not TLL, but who cares about the techincal details!!
Step 1: The Materials
This project only requires a few parts:
1 Breadboard, maybe 2 - It should have atleast 50-60 rows
2 74xx AND chips - I used the 74hc08
2 74xx XOR chips - I used the 74hc86
1 74xx OR chip - I used the 74hc32
1-2 DIP Switches - I used 2 8 switch DIP switches (I'm gonna expand to 8 bits)
8 1K ohm -or greater- resistors
Lots of wire - Don't yell at me but I use bare copper! Its a bad habit, (some may argue that it's a dangerous one) I know, but I don't care!