I did some more poking around the memory and it’s time for some proper answers: the lower four bits of $19 control volume and the lower four bits of $15 control tone. Writing $F0 is silent because it sets the volume to 0. Although, I’m not exactly sure how the bits of $15 work or…
Author: Jacob
Learning Assembly, Part 2 #10
Today I continued investigating how sound output works. It seems that memory addresses $15 and $19 produce sound, but only when both are non-zero.
Learning Assembly, Part 2 #9
Today I reviewed the 2600’s memory map. I want to make a program that finds the addresses which control audio output. I know I could just look it up, but I like the mystery.
Cube Matrix Rain
I made a demo with PICO-8’s new web version! Here’s the link if you’d like to run it.
Learning Assembly, Part 2 #8
Today I practiced addressing modes with some simple instructions. One thing I noticed is that there are no instructions to increment or decrement the accumulator. It seems weird, like why not?
Perhaps
Which will you choose?
Learning Assembly, Part 2 #7
Today I reviewed addressing modes. Then I got sidetracked. In part 1 #7, I discovered that I got a buzzing sound when I wrote #$FF into all the memory addresses. I decided to investigate by trying other numbers. Here’s my results so far: #$FF Buzzing #$FE Clicking #$FD Square wave #$FC Higher pitch square wave…
Learning Assembly, Part 2 #6
The memory cleaning program is working! Last time around I exclusively used Dasm and Stella to assemble and run the code, but maybe this time I’ll use 8-bit workshop. I wish I could get a real Atari 2600. It’d be so cool to see my code running on real hardware.
Typing Test
What kind of game can I make in 10 minutes? Allow me to introduce you to Typing Test, the latest advancement in typing skill assessment for Windows.
Learning Assembly, Part 2 #5
Alright, I’m coding! I wrote a program which clears the memory. For code editors, I’m just going with Vim and Comic Sans. Maybe I’ll eventually get around to trying something else.
Empty Airplane
Today I had a burning question: what kind of game could I make in 2 hours? Here it is: Empty Airplane.
Learning Assembly, Part 2 #4
Ok, I’m about to get coding, just reviewing the processor carry and overflow flags first. I’m also thinking about which coder editor to use. I normally go for Vim, but maybe I’ll use something else this time.
Learning Assembly, Part 2 #3
I’m reviewing the 6507 processor flags and registers. I’m interested in the stack pointer register. Last time around I hardly noticed it and it seems super useful.
Learning Assembly, Part 2 #2
Today I completed an overview of the Atari 2600 hardware and a review of binary numbers. I could probably skip to where I left off and review as needed, but I don’t want to miss anything obvious and waste hours trying to find the figurative semicolon. Also, everything makes more sense this time around. (Sidenote:…
Learning Assembly, Part 2 #1
It’s time to continue learning assembly! I’m going back to the beginning of the course, although I may skip ahead. I’ve just rewatched the introduction and I’m so hyped to be back!
Spray Paint v1 (PICO-8)
Spray Paint in PICO-8! Spray Paint is a drawing application for PICO-8. It’s like the Airbrush tool in Microsoft Paint.
Playing “Portal 2”
I just finished playing Portal 2. Wow, what a cool game. And so different from Portal 1. Before I get to the comparison, here’s some of my favorite things about Portal 2 (spoiler warning): The massive areas. Seriously, I could just look out into the largest warehouses ever. Are large areas like this common in…
Mini Blender Renders, #7
This one is based on a memory I have of Sears. I have no idea why they had washing machines right at the front entrance, but I think it looks cool.