Pamac > Pacman

I must say that I much prefer the Pamac CLI package manager to Pacman. It’s much more intuitive and I’m glad that Manjaro includes it by default.


Arduino Pong

This is a simple pong game I created for fun for the CICS 290M Makerboard running Arduino software. The board is part of the CS Make course at UMass Amherst.

Below is the source code, it’s also available on GitHub.

// Imports
#include <Adafruit_SSD1306.h>

// Globals
#define UP_BUTTON 34
#define DOWN_BUTTON 0
#define RESET_BUTTON 35
#define BUZZER 17

// Game State
int score = 0;

// Paddle
int paddle_pos = 32;
int paddle_velocity = 1;
int paddle_height = 16;
int paddle_width = 4;

// Ball
volatile int ball_x = random(10, 80);
volatile int ball_y = random(16, 48);
volatile int ball_radius = 3;
volatile int ball_velocity_x = random(1, 3);
volatile int ball_velocity_y = random(1, 3);

Adafruit_SSD1306 lcd(128, 64); // create display object

// Callbacks
void IRAM_ATTR moveUp() {
  if (paddle_pos >= 0) {
    paddle_pos -= 1;

void IRAM_ATTR moveDown() {
  if (paddle_pos + paddle_height <= 64) {
    paddle_pos += 1;

void IRAM_ATTR restart() {
  if (gameOver()) {
    score = 0;
    ball_x = random(10, 80);
    ball_y = random(16, 48);
    ball_velocity_x = random(1, 3);
    ball_velocity_y = random(1, 3);
void setup() {
  pinMode(BUZZER, OUTPUT);
  pinMode(UP_BUTTON, INPUT);
  lcd.begin(SSD1306_SWITCHCAPVCC, 0x3C); // init
  lcd.clearDisplay(); // clear software buffer
  attachInterrupt(RESET_BUTTON, restart, FALLING);

// Test if coordinates are out of bounds
boolean yIsOutOfBounds(int y) {return y > 63 || y < 0;}
boolean xIsOutOfBounds(int x) {return x > 127 || x < 0;}
boolean outOfBounds(int x, int y) {return xIsOutOfBounds(x) || yIsOutOfBounds(y);}
boolean gameOver() {return ball_x + ball_radius >= 127;}
boolean ballPaddleCollision(int x, int y) {
  return (x > 128 - paddle_width) && (y < paddle_pos + paddle_height && y > paddle_pos);

void drawPaddle(int x, int y, int width, int height) {
  lcd.fillRect(x, y, width, height, WHITE);

void ding() {
  ledcSetup(0, 5000, 8);
  ledcAttachPin(BUZZER, 0);
  ledcWriteTone(0, 500);
  delay(50); // 500Hz for 0.05 second
  ledcWriteTone(0, 0); // buzzer off

void drawBall() {
  lcd.fillCircle(ball_x, ball_y, ball_radius, BLACK);
  if (xIsOutOfBounds(ball_x + ball_radius) || xIsOutOfBounds(ball_x - ball_radius)) {
    ball_velocity_x *= -1;
  if (yIsOutOfBounds(ball_y + ball_radius) || yIsOutOfBounds(ball_y - ball_radius)) {ball_velocity_y *= -1;}
  if (ballPaddleCollision(ball_x + ball_radius, ball_y) || ballPaddleCollision(ball_x - ball_radius, ball_y)) {
    ball_velocity_x *= -1;
  ball_x += ball_velocity_x;
  ball_y += ball_velocity_y;
  lcd.fillCircle(ball_x, ball_y, ball_radius, WHITE);

void loop() {
  // Check if Game is over
  if (gameOver()) {
    lcd.print("Score: " + String(score) + "\nPress bottom button \nto restart.");
  // Check for button presses
  if (!digitalRead(UP_BUTTON)) {
  if (!digitalRead(DOWN_BUTTON)) {
  drawPaddle(0, ball_y - (paddle_height / 2), paddle_width, paddle_height);
  drawPaddle(127 - paddle_width, paddle_pos + paddle_velocity, paddle_width, paddle_height); 

Signal Foundation Donation

I’ve decided to set up a monthly donation to the Signal Foundation. I’m not the biggest fan of Signal and I’ve been critical of the fact that it relies on central servers that can be shut off at any time.

But none of the peer-to-peer apps I’ve tried (such as Tox) seem competitive in this space. I need something I can give a non-technical friend and not have them feel like its a downgrade from WhatsApp.

For now I’m going to stick with Signal but I’ll keep an eye on some other promising projects like Matrix.


Switching to Krita from GIMP

I’ve been using GIMP for the last couple of years, but since I’m on KDE Plasma I decided to give Krita a try.

It’s actually very capable and I’m going to try using it in lieu of GIMP for a little while.


2020 Recession

There seems to have been lots of talk of an impending stock market crash recently. Some people seem to be absolutely certain of it for reasons such as the inverted yield curve, high PE multiples, and the trade war with China. I’ve even heard people talk about the “2020 recession” as if it has already happened.

Personally, I’m skeptical. I don’t think there is any greater risk of a market downturn today then there was 5 years ago. Everyone knows that the yield curve has inverted and that inversions have historically preceded recessions in the United States. But the expectation of an upcoming recession is already priced into the market.

Similarly, the risks associated with the Chinese trade war have also been priced in.

Now I’m not saying that there won’t be a market crash, but I am saying that if there is one the cause will be something that is not currently priced into the market (in other words, something that isn’t receiving 24/7 news coverage).


Debian 10 “buster” is released!

Debian 10 “buster” is released!


Charlie Munger interview

I always appreciate Charlie Munger’s bluntness in his interviews. It’s quite the contrast to Warren.


Bitcoin is still bad

So it’s been a while since I last purchased something using Bitcoin and I wanted to see if the process had become any less painful today. I decided that I was going to purchase a $10 item at a shop that accepted Bitcoin.

I head on over to my Coinbase account and purchase $10 of Bitcoin. Due to fees the amount I actually got was only worth $8. Okay, I buy some more to make it $10, then I try to send the money to the address I was given by the shop. Turns out that Coinbase doesn’t actually let you send Bitcoin to non-Coinbase users anymore unless you wait 12 days after you purchase it. Even if I could send the money, the estimated fee was over $3 (30% of the transaction).

I ended up paying with PayPal and have asked Coinbase for a refund on my Bitcoin purchases.


Delta Chat

I recently learned about a new messaging app called Delta chat. It is based on top of SMTP/IMAP and works with an existing email account so you can chat with anyone who has email already (everyone?) regardless of if they have Delta chat.

Basically, it is an email client that uses a UI similar to most chat apps. I think this is better than something like a Jabber client because nobody actually has Jabber accounts anymore, but email is still ubiquitous.

There are some problems I foresee:

  • Many free email providers limit messages to 200-300 per day, which may be a problem for some.
  • Depending on the email server messages can sometimes take quite a long time to be received.

This isn’t the first version of this idea that I’ve seen. There are other apps like MailTime but Delta chat is open-source at least and has mobile and desktop clients.


Bookmarking Service

I am skeptical of all of these cloud bookmarking services that have started popping up. Some examples are Pocket, Wallabag, and Instapaper.

It seems to me that if you use these services as advertised (bookmarking articles you don’t have time to read at the moment) then you are going to end up with a library large enough that you will never have enough time to read it all. Additionally, most news content is only relevant for a couple of days or less, so I suspect it would just end up sitting in your bookmarks never getting read.