Sniffer Air Quality Monitor

(DIY) COMMODORE VIC-20 GAME CARTRIDGE 8x 8KBYou can make your own custom Commodore VIC-20 Multi Game Cartridge. (8KB 8 games) (Total 64KB)Hello,This is a tested and working project. (Tested on a NTSC Commodore VIC-20 plugged to a C64 PSU)COMMODORE VIC-20 Cartridge is an Easy DIY project, all components are through hole, marked on the PCB, Easy to solder, Easy to make ;)Select 8 of your favorite 8Kb games and make your own custom Commodore VIC-20 Cartridge. This Commodore VIC-20 cartridge can be used for only 8KB ROMs. This is a simple, DIY multi game Commodore VIC-20 cartridge. It has 8 games capacity each 8 kilobytes, total 64KB.This PCB is also suitable for making 8 KB single-game cartridges. DIP switch is not used when using as a single-game cartridge.There is sample 27C512 binary eprom image file to test the cartridge, you may find the file on bottom of this page. You can find many different ROM files on the internet by searching "Commodore VIC-20 ROMS" or "Commodore VIC-20 Tosec" ROM files bigger than 8 kilobytes are not suitable for this cartridge, you can use only 8 kilobytes (8,192 bytes) ROM files.If your ROM file is 2 bytes more than 8.00 KB (8,192 bytes), it has an Address header for loading. you should cut (remove) these first two bytes from the ROM file, usually like "00 A0" or "00 60" or "00 20" or "00 40". These two bytes indicate the start of loading the memory address. You can do this using a "HEX Editor" program.You should append the 8 Kilobytes 8pcs. ROM files each other, reaching to the size of EPROM capacity, by using a "HEX Editor" program. EPROM must be fully filled from $0000 to $FFFFIt will be easier to make and use the cartridge if you choose all 8 ROMs with the same starting address like "A000". you won't need to solder the male headers, just short Block-5 for A000, short Block-3 for 6000, short Block-2 for 4000, short Block-1 for 2000Note-1: Depending on whether your VIC-20 computer is NTSC or PAL, you should choose the appropriate games.Note-2: Some ROMs do not start automatically. You have to use the SYS.... command to run the game on such ROMs.3D printable standard Commodore VIC-20 cartridge box(Needs holes for DIP switches)https://www.thingiverse.com/thing:69261Please choose: Edge connector YES and Bevelling Yes (30°)COMPONENTS:27c512 (W27C512) DIP282 Row 6 Pin 3P Positions 2.54mm Pitch DIP Switch100nf Ceramic Capacitor (104)3pcs. 10K 1/4 Watt ResistorsDIP28 WIDE IC SOCKET (optional)2x4pin 2.54mm pitch Male HeaderJumper CapRight Angle Tactile Button (For Optional RESET Button)You will need a programmer for EPROMIn order to protect your electronical devices, always turn off your Commodore before connecting or disconnecting the cables or any other device.Gerber files can be changed at any time. Before paying for the PCBs, be sure to update your orders!As you can see I have uploaded many projects and I am still working on new projects. If you have any questions, please look for answers online. Unless I specify explicitly, all my projects are tested and confirmed to work under normal circumstances before being shared. I'm sorry I didn't have enough time to answer all the questions.Use this PCB at your own risk !Have funThank you.

drv8825 shield for cnc & 3d printer+ case 3d printer for drv8825 shield

MIDIFART is a pocket midi controller designed for Arduino Promini that supports five analog potentiometer, 10 buttons, 1 bank button, some modules and midi output capability via 3.5mm TRS cable for sending data out to hardware synthesizer or midi device, and some modules like ultrasonic sensor and LCD display. For programing code can be done with arduinoIDE. The PCB board also support Arduino Promicro as midi device for software controller but sadly you don't have full features like some optional module but it is more than enough for backing up your task.I used this controller for my synthesizer and music software, because today controller out there too big and lack some features like battery powered capability although there are some may still required wireless connection or just usb port as main connection and power source, but old hardware still used wired connection as comunication between the devices. So this project i made just solved my problems and who's interest in my project can build it too. Just visit my Github repository for detail information about pograming code, case and required components. And check demo video.

The HB6809 is a mini ITX form factor 6809 based open expansion computer. there are four expansion slots available which are pre-addressed in to 4K sections, providing enough space to build fairly versatile modules. Currently there is a bare bones serial module but more modules are in the works for sound, traditional HID devices like keyboards / mice / controllers, and graphics. You can download the full project files schematics and more on the GitHub or Hackaday.io sites for this project.The serial expansion card is also available as a shared project as well, though the schematics are simple enough the serial controller could be built on the prototyping area of the main PCB as well.

To create this project I was inspired by the ability to synthesize digital circuits using the Verilog and System Verilog languages.From my own experience, I would like to note that many industrial controllers or programmable relays use “Functional block diagram” semantics as a description of control system algorithms. Naturally, the experience gained with this board can be easily used in industry to obtain reliable, efficient and inexpensive solutions.But and not only in industry.Next in the package Examples there are examples of synthesized circuits. I am grateful to everyone who has read up to this point. For questions and suggestions, write to the email address: daineko.a32@mail.ru P.S. All the best and fresh cookies!

In this article "How to Controls WS2812B Using ESP-01 Arduino (ESP8266)". I made a custom module for the WS2812B LED using the ESP-01. With this module I can make various creations using the WS2812B LED. Among them are RGB LED Strip, RGB LED Animation and RGB Matrix. And in this article I will create an RGB Light Pocket using the WS2812B LED Matrix. I will use this LED for photography lighting. What I hope is, this LED can give a unique impression from the photos I take.Component and Material Components for the ESP-01 modul :4* SMD Resitor 10K Ohm2* SMD Capacitor 10uF1* Regulator 3V32* 1x4 Female Header1* ESP-01Material :1* Modul WS2812B esp-011* Modul Charger Battery1* 8x8 Martik LED WS2812B1* Battery 186501* Battery Holder1* Switch ON/OFF2* Push Button4* 3mm Screw4* 3mm Mur2* 1cm Spacer2* 0.5cm SpacerCableDouble tapePCB HoleBox DesignThe box for this LED pocket I made using a 3D printer. The material I use is PLA. You can see the Box design below. I designed this box on onshape.com.WS2812B ESP01 Module Schematic and LayoutThis is the basic schematic for using the ESP-01 module. The 10K resistor is used as a Pull UP in some of the PINs for the ESP-01 configuration. There are 2 buttons, namely the reset button and the Flash button which are connected to the GPIO0 PIN. With this button I can change the ESP-01 mode to Programing mode or boot mode. The 5P Male header is used to program the ESP-01 by connecting it to USB to Serial. 3P Male Header is used for additional PIN if needed. 2P T-Block for Power supply. 3P T-Block for WA2812 LED. IC 1117 is used to lower the voltage from 5V to 3V3 to supply the ESP-01. You can see the layout and schematic in the image above. And below you can download the original Schematic and Layout file. You are free to use or change the files that I provide.AssemblyTo simplify the assembly process, I removed the connector component on the WS2812B module. for installation I directly solder to the PCB. And here is the installation scheme. You can follow this scheme to assemble all the materialsSoftwareThe software that I made is quite simple. so there are several colors that I provide. To change the color simply press the mode button once. You can add any other color you want, just by modifying a few lines of code.Video

DESCRIPTIONI was fascinated by this type of gearbox and always wanted to make one. This type of gearbox is one of the most used in industrial robots. This type of gearbox only has a single reduction (in this case 2 because of the belt reduction) with a very high reduction ratio. Because of the single stage reduction there's almost no tolerance/play between input and output shaft. Conventional gearboxes use more gears to achieve the same reduction ratio, the tolerances between the gears add up resulting in greater tolerances/play between the input and output shaft.Video:Thank you to PCBWay for sponsoring this project. More info about them can be found in the speed controller section further down.Here are some specifications of the gearbox:Max tested torque at 12V: 41.3kg*cm or 4N*mReduction ratios:Circular spline teeth amount: 50 teethFlex spline teeth amount: 48 teethSmall GT2 pulley: 16 teethBig GT2 pulley: 36 teethReduction ratio strain wave gear: (48 - 50)/48 = -0.04161/0.0416 = 24.038Reduction ratio = 24.038:1Reduction ratio belt drive: 36/16= 2.25Reduction ratio = 2.25:1Total reduction ratio = 54.0855:1Electrical specifications:Motor type: 775 brushed motor (see parts list)Motor Voltage: 0-24VDCIdle power consumption at 12V: 10WPCB rated voltage: 12VDCPCB rated voltage with jumpers for Arduino power supply removed and replaced by a separate DC-DC converter module: 24VDCWorking principleA strain wave gearbox has 3 main components:-Wave generator-Flex spline-Circular splineStrain wave gear working principle. Picture source: Wikipedia.orgThe wave generator (green) generally is the input side of the gearbox and has the highest RPM. The wave generator is being used to deform the flex spline and make the teeth interlock with the fixed outer circular spline (blue). The flex spline (red) is generally the output of the gearbox and has the lowest RPM. One full rotation of the wave generator will move the flex spline 2 teeth in the opposite direction.Circular, flex spline and wave generator designThe design of the teeth for the circular and flex spline turned out to be a little harder then expected. I originally wanted to use double helical gear generator to create the teeth but the teeth ended up interlocking over the complete circumference of the splines, even with a 4 teeth difference between them. Then I tried regular spur gears but these gave the same problems as the double helical teeth. It turns out strain wave gears don't use regular teeth but a much shorter and more straight tooth profile.After the tooth profile was figured out I 3D-printed a first test with a flex spline in PLA. This initially seemed to work pretty good but after a few minutes of turning the flex spline made a few weird noises and pretty much exploded. So this was not going to work. Then I tried printing it TPU filament (flexible filament) which worked a lot better. The dimensions and structure of the flex spline and wave generator needed to be modified a bit in order prevent the flex spline from slipping inside the housing (tighter tolerances needed).The wave generator originally used 4 bearings to push the flex spline in the outer circular spline but when I switched the material of the flex spline from PLA to TPU I changed this number to 6 to make the contact area bigger and prevent slipping of the flex spline.PerformanceOriginally the limiting factor of the gearbox was belt reduction used to drive the wave generator. After changing out the plexiglass lid for a 3D-printed lid and adding an extra motor spacer between the case and motor this issue was resolved. The limiting factor now is the motor itself in combination with the reduction ratio of 54:1. The strain wave gearbox has a stall torque of around 41.3kg*cm or 4N*m.Speed controllerFirst of all a big thank you to PCBWay for sponsoring this project. Due a price drop in raw materials, PCBWay can now provide PCB's at a reduced price. Use my referral link to get a 5$ discount when you sing up as a new user: https://www.pcbway.com/setinvite.aspx?inviteid=586251To control the speed and direction of the motor I designed a custom Arduino Nano based PCB. The PCB features a reverse polarity circuit, a voltage divider to measure the supply voltage, some resistors for LEDs and some header pins to connect the PCB to the IBT2 motor driver.The gerber file for the PCB can be found in the files section on this page.

Hello,This board has been tested on the Amiga 500 port-1 connected with a PS/2 mouse and standard joystick. (Pressing fire button activates joystick, pressing any button on mouse activates mouse.)If you have a PIC16F628(A) and a PIC-Programmer, you can make your own Amiga PS/2 mouse converter adapter, with this circuit-board easily.REV.3 also contains an input for standart 9 pin Amiga joystick. This dual-input adapter acts like a Y-Cable that can be used to simultaneously plug both PS/2 compatible mouse and 9 pin standart Amiga joystick to your Amiga computer. Switching between joystick and mouse is easy; Pressing fire button activates joystick, pressing any button on mouse activates mouse.This Amiga PS/2 Mouse Converter adapter supports; three mouse buttons, most of optical PS/2 mice and some of USB mice (supporting PS/2 communication protocols) (with a simple and cheap USB to PS/2 converter.)You need to download .HEX file and program it in to PIC16F628(A), from this link,https://archive.org/download/amiga-ps-2-mouse-pic-16-f-628/AMIGA_PS2_MOUSE_PIC16F628.zipCOMPONENTS:PIC16F628A or PIC16F628DIP18 IC SOCKETDB9F D-SUB 9 PIN SOLDER TYPE FEMALE CONNECTOR - You can remove the metal cover if necessary (for A600)DB9M D-SUB 9 PIN SOLDER TYPE MALE CONNECTOR6PIN RIGHT ANGLE PS/2 FEMALE PCB TYPE MINI DIN CONNECTOR100nf CAPACITORIn order to protect your electronical devices, always turn off your Amiga before connecting or disconnecting the cables or any other device.Gerber files can be changed at any time. Before paying for the PCBs, be sure to update your orders!Use this PCB at your own risk !Have funThank you.

This is the best version of my 18 key keyboard I have built so far. I peak at 100wpm on this. Mainly though it is the feeling of an almost total lack of effort needed to type on it that is the most striking. Pictures and information on the board and layout can be seen here:Layout: https://www.youtube.com/watch?v=5RN_4PQ0j1ABoard: https://www.youtube.com/watch?v=0d8mjsVgk1k

Watch Full TutorialToday we will take a look over what is FOC control, create an awesome PCB and control a triple phase brushless motor with it at very low speeds and precise movement. FOC is a very common and useful method of controlling brushless motors and is used a lot in robotics. I want to explain to you how it works, how the PCB is made and show you the code and an example for an open loop control and then a closed loop control using a magnetic encoder which is also very important. As always, you can get from below the PCB files, the schematic and everything you need to make the same project. So guys, let’s get started.Full part list here.Today we don’t make a normal brushless motor controller or so-called ESC. We make a controller that is called FOC and stands for field-oriented control and for this project I’ve made a PCB that you could download from below and order it at PCBWAY as always, and make the same project. It has everything you need and it has screws for the motor, a smaller PCB for the magnetic encoder which is very important, it also has the triple phase driver and an ATMEGA328 microcontroller and a bunch of inputs and outputs. So get my files and go to PCBWAY.com and click the quote now button. Insert the PCB size and select the amount and solder mask color. Click save to cart and on the next page upload my GERBER files. Place the order in just a couple of minutes and receive perfect PCBs. They look amazing with the red solder mask. I’ve made the design in such a way that later we can cut the tiny part and place it over the big PCB.

Purpose of the projectMy project is about preventing old hardware from being abandoned. I decided to make it because original Memory Card for PS1 are not being manufactured anymore. Used one are often very expensive (and in unknown conditions) while cheap import clones do not work nearly as well.With PicoMemcard instead, you can build a USB-compatible MemoryCard with unmatched performance! Best of all? It's cheaper than buying a used original Memory Card!FeaturesAble to faithfully simulate PSX Memory CardUSB connection to import/export savesAllows to copy saves to/from any other memory card (using original PSX file manager)Allows to play burned CDs (thanks to FreePSXBoot)Cheaper than an original memory cardCan store hudreds of memory card imagesHow it worksIt works by using the PIO (Programmable I/O) funcitonality of the Pico to intercept the protocol used by the PSX to communicate with memory cards. By using a carfully crafted piece of software that I developed, it's possible to trick the PSX into beliving a real memory card is plugged in and simulate it using only a Raspberry Pi Pico and a hardware interface to the PSX.As for the hardware interface, it's possible to use a broken controller cord, a broken memory card or the PCB I personally designed for this purpose. It's also possible to 3D-print a support and simply use some copper wire to create the right contact pattern.Code and schematicsAll the code for the project and the schematics has been published as open source on my Github repository:https://github.com/dangiu/PicoMemcard3D-printed caseI've also designed a custom enclosure that can be easily 3D-printed and helps inserting the PCB in the correct position.https://www.thingiverse.com/thing:5488778Video?

From the late 1800s to the late 1900s, a typewriter was one of the best tools for writing documents. Sadly, they were largely rendered obsolete by the rise of home computers. I didn’t grow up using a typewriter, but a couple months ago I bought a Brother AX-25 electronic typewriter. It uses a daisy wheel (a spinning wheel with letters molded into it) and a motorized hammer to type text, rather than type bars (or strikers) like in a traditional typewriter. The sound it makes is unmatched even by the clickiest of keyboards. Each keypress results in a short buzz as the motor selects a character, followed by a satisfying clack. The AX-25 has a 16-character LCD, 128 kB of ROM for the typewriter’s firmware, 128 kB of storage, and 16 kB of RAM.These specs are pretty terrible by today’s standards. Luckily, it’s easy to repurpose old technology with open-source hardware! That’s why I used an Arduino and a Raspberry Pi to turn my typewriter into a Linux terminal.InspirationBack in high school, one of my friends was working on making a computer using a Z80 for a school project. He had it set up on a few breadboards in a briefcase, and after we talked about it for a bit, we decided that we would try to put it in an old typewriter. We wanted to make our own Commodore 64. We gutted an old electronic typewriter, but never got around to putting the computer in it. For the past 6 years, I've had that typewriter's shell sitting in my room.For a while, I wanted to turn the typewriter into a cyberdeck. I planned on putting a screen in it, and a Raspberry Pi with a hefty battery. I had that idea rolling around in my head until a couple years ago, when I saw CuriousMarc's video about his teletype turned into a Linux terminal. I wanted to do the same to a typewriter, but I never had the time to do it and couldn’t find a typewriter at any thrift stores. After graduating from college, I finally had enough spare time, and knowledge, to turn a typewriter into a computer.What it can doI can use all sorts of Linux commands, most CLI programs will work, but anything with a text-based interface (like Vim or Emacs) won’t work. By processing the escape sequences that the Raspberry Pi outputs, I can automatically toggle the typewriter’s formatting features. It can also print ASCII art! Here’s a video of it printing some art I found online, and some that I made using an ASCII art generator:Reverse-engineeringThe typewriter’s keyboard is wired up in an 8x11 matrix, and it connects to the typewriter using two connectors, one for the rows, and one for the columns.The keyboard connectors with jumpers to my circuit plugged into them.When you press one of the keys, it connects one of the row pins to a column pin, which the typewriter then detects. To figure out which pair of pins each key corresponds to, I connected each pair by hand one at a time, and wrote down what key was printed. I did this until I had the entire matrix mapped out.The typewriter matrix's layout.The typewriter uses a 7805 linear regulator to power its 5V components, and I was able to locate an unused 5V pad and ground pad that I can tap into to power my circuit. I had to add a heatsink to the regulator to accommodate for the increased power consumption of my circuit.Controlling the typewriterThe Arduino code is available on my GitHub repository if you’d like to look at it in more detail! My Arduino controls the typewriter using two multiplexers, one connected to each of the keyboard connectors. The multiplexer’s signal pins are connected so they can be used to connect pairs of pins on the keyboard connectors together. To send a key, the Arduino selects a pin on each multiplexer to connect them, which tricks the typewriter into thinking that a key has been pressed.My prototype for the typewriter control circuit.The Arduino is connected via serial to the Pi, which has the serial console enabled on its UART pins. I chose to use an Arduino in addition to the Raspberry Pi because I’m more familiar with them, and it makes interfacing with the Raspberry Pi’s UART console much easier. The Arduino and the Raspberry Pi communicate at a rate of 120 characters per second, but the typewriter can only type 12 per second. To prevent long messages from getting cut off, I added serial flow control to my code. This allows the Arduino to tell the Pi when to start and stop sending text. The Raspberry Pi is running Raspberry Pi OS Lite, since I only need access to the terminal.KeyboardTo scan the keyboard, I used essentially the same circuit; two multiplexers, one for the rows, one for the columns. The Arduino scans the keyboard one key at a time by selecting a channel on each multiplexer. When it detects that a key has been pressed, it sends that character to the Raspberry Pi so it can be processed.My prototype for the keyboard scanning circuit.I could have used the typewriter’s original keyboard for this project, but I chose to replace it with a custom mechanical keyboard with Matias Alps switches, which are super clicky and should feel great to type on!The custom keyboard layout I designed for my typewriter.ConclusionBy turning my typewriter into a computer, I was able to recreate the experience of using a teletype. Now I know what it was like to use Unix in the 1960s when it was originally being developed! The custom mechanical keyboard feels amazing to type on, and is a huge upgrade over the mushy membrane keyboard it originally had. With these upgrades, my typewriter is much more powerful now!