Too Many Ideas

My mind is overflowing with ideas for the Hack Minimax.  Not only am I redesigning the memory mapping unit, I am also trying to figure out how I will generate video and generally communicate with the real world.  I also have plans to add another 8 bits to the microcode word, as my current 24 bits are packed extremely tight.  Also included in my thoughts are a retarget of the classic Small-C compiler and an assembler.
In other news, I finished my SUBLEQ simulation.  I found a 74181 Logisim library and have designed another vital chip - the 74161.
As to the calculator, I will be pretty busy this week but hope to start redesigning the interface over the weekend.
See you soon!

I'm back! (Again)

Sorry that I haven't posted for a while. I'll try to keep up.

I have decided, after reviewing the shortcomings of the previous platform (most notably that it doesn't support interrupts), to go with a different architecture. I apologize to all that came from the TECS forum and I promise that I will eventually write a Hack emulator.

In lieu of the Hack microarchitecture, I am going to use a 6502-based microcoded architecture.  For those who don't know, the 6502 is an 8-bit microprocessor that was very popular in its day.  I have a very nice design for the microarchitecture I just made about 30 minutes ago that fits into a 24-bit horizontal microcode.

I am also going to call a halt to all hardware until I inventory my already-owned chips, design schematics, and simulate them successfully.  To that extent, I am learning how to use Logisim by designing a test 8-bit SUBLEQ computer.  After that, I will need to design simulations of each individual MSI chip, then combine them in my simulation.

While I haven't posted in a while, I've been doing some thinking about the capabilities of the HM. I am designing a paging system and I/O extenders.

See you (hopefully) soon!

I'm back!

I haven't posted for a while, but I actually have gotten a lot of the computer done.  However, new changes in the project will force me to start over on some of the pieces:

1. I had been wiring the Hack Minimax by grouping each register together.  However, this will be a nightmare to wire, so I am deciding to rather create miniature 4-bit "slices" of  the computer.  Not only will this simplify the wiring, it will grant a degree of extensibility to the computer.  I can run programs with only 8 bits done, and if I ever need to, I can always extend the computer to 24 bits or beyond.
2. I had been using the 74181 as my ALU, but the 181 doesn't support some of the operations the Hack Minimax needs.  Most importantly, it only allows some operations on some registers.  I will rather be constructing the ALU out of lower-level gates.

I will post some pictures up soon, but I will not post them for the next 2 weeks while I am at summer camp.

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.