I also got another box of stuff from Mouser, some new wire cutters, the giant plastic container for the computer, and other various things.
Those are mostly giant 800-point breadboards in the plastic container.
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Left: The huge power supply.
Right: The smaller one.
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With my new soldering iron from the Shack, I was sure I would get soldering right. Of course, the tip managed to oxidize in the time it took me to strip the end off a wire. I have completely given up on soldering at this point.
Now begins the search for a DIP-pin enabled pushbutton switch.
With a power supply, I can finally begin the construction of the CPU.
Right: A cute 14-pin DIP 7-segment LED display. I have two.
Hey, are you still working on this? I'm working out of the Schocken book, but I know next to nothing about EE. I still want to make a hardware implementation, but I've had trouble figuring out where to start.
ReplyDeleteI tried building an ALU with some 7600 series and a breadboard, but I ordered the wrong display, and I'm worried I'm going to fry the circuits when the new one comes. I didn't use any resistors or capacitors; I just got some wires and hoped electricity worked like it does in minecraft ;P
Yeah, I am. I haven't posted in a long time, but I actually have a lot of the computer done. I will probably not use any resistors in my version of the ALU, but I don't have a display hooked up. Are you using an LED display? If so, you are probably going to want to put resistors between the LED and the power to limit the current; otherwise, the LEDs will be fried. It's nice to know someone is actually reading this!
ReplyDeleteYeah, I'm using a simple 7-seg LED display for the ALU, so I'll go get some resistors. I'm mainly having trouble with the 7447, but I think I may have gotten another chip confused with it. I'll see if I can figure it out... When you can I'd love to see what you've done, I was worried you might have dropped the project. Glad to know you're still working on it!
DeleteThe 7447 is a BCD decoder, while your ALU outputs numbers in binary. If you want the result as a decimal, you're probably going to have to use a microcontroller or the like. It you just want the numbers to come out in human-readable form, you should use a hexadecimal display, though I've been looking for a few and haven't found them yet.
DeleteI wasn't sure how I was going to get the ALU outputs to display easily, so I decided to start off with a 3-bit ALU so it could work with the 7447. That should work, right?
DeleteRegardless of whether I can integrate it with the ALU, my main problem is getting the 7447 to do *anything*. I got some resistors and hooked it up to the 7-seg, which works fine when tested manually, but the 7447 won't sink any current. But I think that's because I'm using too much voltage; it says its max voltage is 5.15 or something and I'm using 6.
I was going to get a 5 volt regulator sometime today and see if it'll work. Hopefully I didn't fry the chip...
Always use 5 volts with the 7400 series. You might want to check all of your chips to make sure they still work. If you do get a 5 volt regulator, make sure it has REGULATED output; if it also has a usb connecter on there, it's fine.
ReplyDeleteI just got an arduino and I'm using the 5v output that comes with, and I got the 7-seg working; the chips are all good, I didn't break them.
ReplyDelete