Category Archives: Computer

Bash-completion, C64 Pico Amplifier and Laser cutting

Worked on bash autocompletion for QP

source below script to get
qp <tab><tab> shortcode

Not happy with both versions yet …

#/usr/bin/env bash

# Version 0.1
qpcompl()
{
  COMPREPLY=($(compgen -W "$(qp | cut -f2 -d \' )" "${COMP_WORDS[1]}"))
}
complete -F qpcompl qp
--------------------------------------------------------------------------------------
# V 0.2
_qp_complete() {
    local cur prev opts
    COMPREPLY=()
    cur="${COMP_WORDS[COMP_CWORD]}"
    prev="${COMP_WORDS[COMP_CWORD-2]}"
    opts="add del"

    case "${prev}" in
        add)
            COMPREPLY=( $(compgen -d -- ${cur} ))
            return 0
            ;;
        del)
            COMPREPLY=( $(compgen -f -- ${cur}) )
            return 0
            ;;
        *)
            COMPREPLY=( $(compgen -W "$(echo add; echo del ;echo "" ; qp)" -- ${cur}) )
            return 0
            ;;
    esac
}

complete -F _qp_complete -o nospace qp

Game controllers : left into right setup

My Bus Manipulator

And a Jigsaw in progress (with our own made clock in the background)

C64 Pico Amplifier

My C64 had a problem with previous attached speaker.
It drew too much current to drive. And random characters where printed.
Choosing another speaker and a minimal amplifier solved the issue.
(Thanks to Bigred finding the problem at Bornhack 2024)

My minimal amplifier for:

Using below mini speaker:

QuickPath and laser cut designs

Today I made a Linux version of Tyrone’s QuickPath tool.

My friend Tyrone came up with a great idea.

A directory switching tool, to move around in often used directories.
You can use a keyword to move around. These keywords are configured in a config file.
Even starting Total Commander with preset directories.
Work/Private/Programming environments.
His version uses PowerShell, but he wanted a multiplatform version, so we have chosen to use Python on both environments.

My version uses Python and Bash.
(Bash is used for a change directory workaround on Linux and bash completion.)

Source will be in Tyrone’s git when finished.

Options:

  • qp – lists config items with number and short key
  • qp 1 or qp c64demo – changes directory to below example
  • qp add c64demo /data/store/git/projects/c64code2024 – add a entry
  • qp del 1 – removes entry
  • qp mc tmp c64demo – starts midnight commander with left and right directories

Tomorrow some laser cutting, so let’s design some things to cut.

  • Jigsaw test – using engraving and cutting
  • Make a front for my bus manipulator
  • Make some cases for the game controllers (These are beta, and will be 3D printed at a later stage. My old 3D printer is slow)

Reverse engineering Newton wars, giving it my own twist.

Saw a cool game a while ago, and found some old code.
There was no schematic, so I had to reverse engineer it using the Arduino code.
This one uses a Micro Pro.

Build a working version, now I can use this as base to create other games.
But first i’m going to rebuild it so it can use Wifi and uses a Lipo Battery. Making it usable without wires.

  • Rotary – set angle/speed (Press resets)
  • Blue – toggle angle or speed ( was rotary press )
  • Green – select digit to change
  • Red – Fire
  • Led – not completely working yet, shows color of player
    Wil be changed to addressable leds with more functions
    (Player color, energy warning and more)

Next to do:

  • Build a Wifi version with Lipo
  • Build permanent version in a case
  • Build 2nd 3th or more controllers
  • Create own games

Bornhack 2023 NFC Badge Display hack

Last week I bought an old Bornhack Badge. I thought it needed a display.

Using a SSD1306 display, and Circuitpython I made this.

( Wooded thingy contains an RFID chip ( Part of my player ))

Library and files needed:

  • font5x8.bin in root of filesystem ( just google for this file )
  • copy of adafruit_framebuf.mpy in /lib
  • copy of adafruit_ssd1306.mpy in /lib

Code: (midway some pixel examples, just uncomment)

import board
from time import sleep
import busio 
from PN7150 import PN7150
import adafruit_ssd1306
import math
import adafruit_framebuf


if True:
    # Fast 400KHz I2C
    i2c = busio.I2C(board.SCL, board.SDA, frequency = 400000)
else:
    # Regular 100kHz I2C
    i2c = board.I2C()


WIDTH = 32
HEIGHT = 8

buffer = bytearray(round(WIDTH * math.ceil(HEIGHT / 8)))
fb = adafruit_framebuf.FrameBuffer(
    buffer, WIDTH, HEIGHT, buf_format=adafruit_framebuf.MVLSB
)


nfc = PN7150(i2c, board.IRQ, board.VEN)

display = adafruit_ssd1306.SSD1306_I2C(128, 32, i2c,addr=0x3c)

assert nfc.connect()
print("Connected.")

assert nfc.modeRW()
print("Switched to read/write mode.")

display.fill(0)

display.show()

#display.fill(0)
#display.text('Hello', 0, 0, 1 )
#display.text('World', 0, 10, 1)
#display.show()
# Set a pixel in the origin 0,0 position.
#display.pixel(0, 0, 1)
# Set a pixel in the middle 64, 16 position.
#display.pixel(64, 16, 1)
# Set a pixel in the opposite 127, 31 position.
#display.pixel(127, 31, 1)
#display.show()

while True:
    display.fill(0)
    display.text('Waiting for card', 0, 0, 1 )
    display.show()

    assert nfc.startDiscoveryRW()

    print("Waiting for card..")
    card = nfc.waitForCard()
    assert nfc.stopDiscovery()

    print("ID: {}".format(card.nfcid1()))
    id = card.nfcid1()
    display.text(id, 0, 10, 1 )
    display.show()

    sleep(0.5)

Not sure about display i2c address? Use below code

import time
import board
import busio

# List of potential I2C busses
ALL_I2C = ("board.I2C()",)

# Determine which busses are valid
found_i2c = []
for name in ALL_I2C:
    try:
        print("Checking {}...".format(name), end="")
        bus = eval(name)
        bus.unlock()
        found_i2c.append((name, bus))
        print("ADDED.")
    except Exception as e:
        print("SKIPPED:", e)

# Scan valid busses
if len(found_i2c):
    print("-" * 40)
    print("I2C SCAN")
    print("-" * 40)
    while True:
        for bus_info in found_i2c:
            name = bus_info[0]
            bus = bus_info[1]

            while not bus.try_lock():
                pass

            print(
                name,
                "addresses found:",
                [hex(device_address) for device_address in bus.scan()],
            )

            bus.unlock()

        time.sleep(2)
else:
    print("No valid I2C bus found.")

Webcam plus OpenCV fun

While attending Bornhack 2024 in Danmark, I came up with the below fun ideas.

Using Python and OpenCV, I made some funny webcam hacks.

Note: My laptop webcam is very bad, a better webcam should give you a more stable result.

First, a virtual workspace flipper. Just using my head movement to flip through my virtual desktops. (Turning left and right)

Next, an image viewer.
Using your head movement up, down, left and right to control the image.
Note : this is not the same movement as above. This won’t use rotation of your head!

Just back from Denmark

The 15th, we got in our car and drove to Denmark.

We went to Bornhack2024, a hackers camp.

Although there are bad hackers (black hat), the term hacker is being used to describe people who are using technology alternative or even hack food and drinks.
Create something new or improve. Mostly using computers, but think of it in a broad way.
Programming, 3D designing or printing. Learning new things.

We (me and my girlfriend) went with Bigred (and his girlfriend) and Tyrone. Both good old friends.

With Bigred I made a mini C64 Badge in the last few months.
With Tyrone I started coding 6502 Machine Language again.
(Planning to release a demo at X2025)

Stuff I did there:

  • Programming demo parts (Sprite multiplexing, Music Sync)
  • Made some demo graphics
  • Programmed some shaders
  • Circuit Python hacking on the Badges, no new one this year 🙁
  • Soldering my Bus Manipulator
  • Python to generate SIN tables (acme output)
    !byte $CA,$FE,$BA,$BE
  • Coding 101 with Tyrone (Acme pipeline, Git and MircoPython on his MCH badge)
  • Drank too much
  • Slept too short
  • Removing gallons of rain water from Tyrone’s tent.
Mini shader in GLSL language

After a week of hacking, we went for a short holiday in Denmark.

Visiting Viking Museums, Old cosy towns, WWII bunkers, the Beach and more.
Driving back to the Netherlands, we visited the only surviving VII-C U-boat in the world.
(Same as I 3D printed for the Uboot game)

Working on a demo part

Started coding a demo with a friend of mine.

I made a part that uses raster interrupts and gives the illusion that the picture is up in the border.

  • Opening the borders
  • Changing the border colour midway
  • Using NOPs to get a stable rastersplit
  • Sprites in the border
  • Fixing the sprite mirroring in the bottom part
  • Learning a lot about bad raster lines, I had to make a lot of workarounds to get it working

Hopefully I’ve got some rastertime left to play music. But I learned a lot!
UPDATE: Yes also with SID music!

Not shown: Bad raster lines, split colors background and bordercolor.
Maybe I’ll add these later.

UPDATE: 20240720

Sprite multiplexing done and self modifying code.

Keyboard switcher part 2

I’ve connected the rotary encoder directly to the zero.
Although many websites state that you need pull-up resistors, there is no need. Just use the internal pull-up resistors in the Pi.

Example code

        GPIO.setmode(GPIO.BCM)					# Use BCM mode
        GPIO.setup(self.24, GPIO.IN, pull_up_down=GPIO.PUD_UP)
        GPIO.setup(self.25, GPIO.IN, pull_up_down=GPIO.PUD_UP)
NOTE: Between 24 and 25 is a GND connection

Besides USB HID below XT, C64 and Amiga connectors will be emulated