A Trip to Radio Shack

Over the weekend I went to Radio Shack for the third time and got a lot of stuff.  This includes TWO 5v power supplies, one huge one that can supply a whopping 18 amps (!) and a portable 3 amp one.

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.

Left:  The huge power supply.
Right: The smaller one.

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.

A Soldering Iron, Part 2

I got another soldering iron.  Of course, the solder will not stick to the PCB.  Back to the drawing board for the regulator.

I recieved a heatsink compound, which I will not be using because the solder won't stick to the PCB!

More Mouser components are coming - a potentiometer for the clock control, a few more ICs, decoupling capacitors, 80 more LEDs, some more EEPROM, and a variety of resistors.

A Soldering Iron: Part 1

I have ordered another soldering iron.

Meanwhile, operations are at a standstill.  Things will be picking up, though, once I obtain a working iron.

Just some notes:

• The 5V regulator will be constructed using the "Manhattan" style of unmarked PCB building.  This will add some extra capacitance to ground, but I'm already adding 200 uF; what more can a few pF do?
• I just got what I hope is my last breadboard, bringing my total up to eight.
• I also received a huge plastic container to be used as the case.
• If anyone can find a place to get 24 gauge solid wire, please contact me in the comments and/or email me.

A picture of the COMPLETED regulator will hopefully be forthcoming.

Parts and a Broken Soldering Iron

All of the materials came Thursday.  Here are some pictures:

And this is what I will use to create the voltage converter:

Unfortunately, my soldering iron broke, so I have to get a new one.  Updates on progress will follow.

The Components are Coming

I have just ordered all the components left to order for the computer.  Hopefully they will come within the next few weeks.  I shipped them using the postal service, so no guarantees.

Pictures will be coming, probably starting with the general-purpose AC line voltage to 5 volt converter.

EEPROM Troubles

All sorts of stuff is coming in, and along with it I realized that I didn't get enough EEPROM.  Good thing it was on the website where I am ordering the rest of my components.

Architecture

That last post had been sitting in Drafts for over 2 weeks, so I felt like I just had to get it out.  Anyway, most of the parts have either been ordered or are in shopping carts.

The general architecture is pretty striaghtfoward.  It was mostly taken from the book The Elements of Computing Systems, by Noam Nisan and Shimon Schocken.  Probably its most attractive feature is that its control logic consists of 2 or 3 ICs containing in total maybe two dozen MOSFET transistors.  Most of the instructions are essentially microcoded.  For example, as long as bit 15 of the instruction is 1, bits 11-6 of the opcode go directly to the ALU.  The computer is a Harvard architecture, but that can easily be modified into a  modified Harvard architecture.

So, anyway, I will be quite possibly posting a variety of pictures at some point.