Author Topic: I've designed a circuit board and soldered all the pieces.  (Read 10937 times)

short fingers or weird angle?

The ALU for my computer is done:





Expecting massive page stretch so click for full view. Didn't have to do any actual physical wiring thank god, this was pre-implementation of pipelining, don't think I have anything after this. The program outputs an address which the harness uses to find an instruction as an input, couldn't find the harness .circ file but all it would do is have a memory lookup of the output ("fetch_addr") and feed that output back into the cpu (as "INSTRUCTION"). If you're not familiar with this kind of architecture: it'll first pass through instruction fetch to get an instruction from the PC, then goes to instruction decoder where it's dissected into parts, looks up registers and passes opcode/func through controller, executes code & then writes back to memory/registers. There's a bunch of extra circuitry to handle immediates (i.e. constants) and program flow (i.e. jumping, returning) but that's the gist of it.

Also the controller was super dumb/tedious to implement as it involved basically hardcoding based on opcode and function code so I didn't put it in any screenshots, but it basically tells the ALU what to do/defines other cpu behavior based on what the operation specified by an instruction is

(but dear lord why would you do this to yourself... this class was the death of me, i couldn't imagine ever doing this for fun)
oh hey logisim and mips and a somewhat recognizable skeleton setup....

did you happen to go to a well known public university with a good computer science division that likes carbonated soft drinks?

how does one design these circuit boards
like is that stuff 3D printed or what

how does one design these circuit boards
like is that stuff 3D printed or what
The program I use is Kicad. I then take those files and give them to Oshpark or Seeedstudio for processing.

Here's a video of the ALU in action:
https://www.youtube.com/watch?v=FYLaWMLSqp8

so what is this board fo-- oh its for a computer

nice

how much flops (floating point operations)
and how much Hz