TI Calculator Link Cable

I got a TI calculator link cable! Now I can write programs for my calculators and run them in emulators!

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Learning Assembly, #11

Today I learned about the Atari’s TIA screen objects. It’s kind of like the TIA chip has presets for sprites and there’s a limited number of settings to configure them. The most interesting screen object to me is the playfield. It’s a per-scanline 20 bit pattern which is either mirrored or repeated for the left…

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Learning Assembly, #10

Today I made a better program to display all the colors! It loops through the scanlines and displays one color per line. It still isn’t actually all the colors; there’s only 192 visible scanlines and the Atari’s palette has 256 colors. Next I want to learn how to display multiple colors per line.

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Learning Assembly, #9

Today I learned more about the Atari’s display timing. It’s weird for me coming from PICO-8, where you can set pixels anywhere and the only limit is the CPU. Comparing the two:

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Learning Assembly, #8

Today I finally got something on the screen! I started with making the background yellow and then I tried cycling through all the colors: It isn’t actually all the colors: there’s a limit on the number of colors per scan line and I don’t know how to do the timing to show all of them.…

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Learning Assembly, #7

Today I fixed a bug with my memory clearing program! I also tried writing #$FF into the RAM instead of 0 and it made a weird buzzing sound!

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Learning Assembly, #6

Today I wrote my first assembly program for the Atari 2600! It just clears the memory, but it’s so cool! Also, the emulator I’m using (Stella) has a debugger mode with a complete view of the memory and registers. I feel like this is a much easier way to learn assembly than going straight to…

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Learning Assembly, #5

Today I started learning about the 6507 processor, how it represents numbers, and its op codes. The 6507 uses two’s compliment to represent negative and positive numbers. I think two’s compliment explains why, in PICO-8, adding 1 to 32768 causes it to go negative. It runs out of bits and carries 1 into the sign…

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Learning Assembly, #4

Today I did a review of binary and hexadecimal numbers! Some notes: to distinguish number bases in Atari assembly, # is decimal, $ is hexadecimal, and % is binary. So #10 is 10, $10 is 16, and %10 is 2.

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Learning Assembly, #3

Today I completed a review of the Atari 2600 hardware! The Atari 2600 is so simple. It’s weird to see a schematic of all the circuits in a computer fit on one page and it’s weird to think that I could fully understand how it works. I’ve always felt like computers were too complex to…

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Learning Assembly, #2

So I made basically no progress today xD I thought I would have more time, but then I didn’t. It’s okay though, tomorrow is a new day.

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Learning Assembly, #1

Today I started Mr. Gustavo’s assembly programming course on Pikuma.com! I’m so hyped! I just completed the intro and I can’t wait to get coding.

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Learning Assembly, #0

It’s finally time to learn assembly! I want to make demos for the TI-83 Plus calculator, which uses Z80 assembly. I’ve only done a little ARM assembly on the Raspberry Pi, but nothing noteworthy. Today I’m finding resources and scoping out the assembly landscape. I know that assembly isn’t portable like C or Python. Each…

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Mini Programs in ><>, #3

Today I made a program which generates an ascii star field, inspired by a program in “Basic Beginnings”.

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Mini Programs in ><>, #2

Today I made something like cellular automata in ><>! It wasn’t working until I figured out that ><> reads characters from the grid as numbers, but stores characters by interpreting the number as an ascii code. So if I try to store 9, it writes a tab character (ascii 9). Adding 48 fixes the problem.…

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Colors Demo (PICO-8)

Today I played with sine and cosine in PICO-8, and it looked cool, so here it is! Press any key (arrows or X/Z) to pause.

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Fr e sh a vo cado

Here’s a meme rendition I made a while ago and forgot to post. Original meme by @Gasoleen.

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Rainy Window (TIC-80)

Today I made a rainy window simulator in TIC-80! Hit escape then “close game” to view the code in the browser! It might not look right on mobile, it’s my first TIC-80 upload, so I’m still figuring out what works. This is a project I’ve wanted to make for quite a while and I thought…

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