Author Archives: Chris McCarty

Getting Fancy with PWM

via SparkFun: Commerce Blog

When you first buy an Alchitry Au or Alchitry Cu board, the default FPGA configuration creates a fancy wave effect on the LEDs. In a new tutorial, we walk through different steps for how to make something like this. It will be a great overview for how to approach a design and various things to consider given that we are working with hardware.

First FPGA Project - Getting Fancy with PWM

July 30, 2020

An initial project using Alchitry's onboard FPGA to manipulate PWM

Learn about pulse width modulation (PWM), pulse an LED and create a wave - all on an FPGA. We'll provide you with the tools you need and show you how to do it!

 

FPGA chip

 

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Autonomous Riding Lawnmower Update

via SparkFun: Commerce Blog

Jesse Brockmann is a senior software engineer with over 20 years of experience. Jesse works for a large corporation designing real-time simulation software. He started programming on an Apple IIe at the age of six and has won several AVC events over the years. Jesse is also a SparkFun Ambassador. Make sure you read today's post to find out what he'll be up to next!

This is the third part of a multi-post series. If you would like to start from the beginning click here to see part one, or here to see part two.


So I finally have been making good progress on this project, and I’m ready to show you the finished product. This is what the electronics look like:

Mower Electronics

  1. 40 A circuit breaker that can be manually tripped to remove all power from control electronics
  2. Standard ground Spektrum RC receiver - the antenna is being propped up for better reception (yes, it is a straw)
  3. My standard V0.1 JRover baseboard
  4. Pololu Simple Motor Controller G2 18v15 x 2 - one for the steering motor and one for the linear actuator on the brakes
  5. Switch on the left is for the motor controllers in #4, and the right switch is for control electronics and shifter
  6. Kill Relay - if power is lost to electronics or microcontroller fails this relay will turn off and will kill the motor by grounding out the magneto for the ignition
  7. Custom perfboard with DC motor driver for shift controller, voltage regulator from 12 V to 5 V for use by electronics and RC servo and connections for linear actuator used for shifting

Some parts of the control system were previously discussed in my last Phase One update, and I am happy to say that after fixing some bugs, the system seems to work perfectly. Along the way I did find some fun issues: When switching from run mode to stop mode the throttle would stay in the previous position and not go to idle, and sometimes the brake would not engage. These are the exact type of issues that make it essential to test and try to find all the bugs before the weight of a 400-pound mower is involved. Any change to the code, even minor, should be thoroughly tested in a safe environment before driving the mower - failure is always an option.

After all the systems were tested on the mower without driving it, the time came to finally drive the mower around under remote control! Unfortunately a snag was encountered at this time and I had to wait a month for some gas engine issues to be resolved.

Here you can see the mower in its current configuration.

Mower Servo Config

This shows the servo that controls the throttle of the mower by replacing the throttle linkage. The servo can also be used to shut off the mower by moving the throttle arm all the way to the left, which shorts out the magneto. A heat shield was added to the muffler to prevent radiant heat from damaging the servo. In the future, a guard might be added over the servo to protect it and make it look more OEM.

Mower Throttle

A guard was also added to the linear actuator for the brake. This helps it blend in better and look more professional (oops, I see the red kill wire needs to be tucked into a wire loom).

Mower Shift Actuator

The shift actuator is shown with the mower in second gear. The selectable gears are second, neutral and reverse. Guides were added to help the shifter into the correct gears without jamming. A potentiometer built into the actuator is used for feedback, which allows the controller to know the current extended length. One feature still needs to be added here to allow detection of the actuator stalling. Occasionally the transmission will still get jammed when going into gear, and that could burn out the actuator quickly if not detected. I will do this using a current sensor, as the power used when an actuator stalls is higher than in normal use.

Mower Steering Wheel

A guard was added for the steering to keep the chain clean, and look more professional. Just to the right of the key in this picture is a strip of RGB LEDs used to show the status of the control system and display any errors.

A kill switch with tether was also added to the back of the mower, but I’m sorry to say I don’t have a picture of it.

Now for the big moment in this project: a wrap-up video montage!

This means that Phase One of my autonomous mower project is (almost) done. As I said in the original post for this series, I was going to move on to an autonomous mower once I was done with this. But as with all things, changes can and do happen. Before building an autonomous riding mower, I’ve decided to test my code with an autonomous electric go-kart!

Autonomous Electric Go-Kart

This is a 1800 W 48 V brushless BOMA brand motor mounted, and a #35 chain ran back to the drive sprocket.

#35 Chain Rack

A Torxis servo is being used to drive the front steering. This servo is very large at 5 inches long, weighs 2.2 lbs and is rated at 800 oz-in continuous torque.

I plan to keep working on the go-kart project until the weather makes me stop. I would like to have it running via remote control before winter hits, but I’m not sure I will make it. I’m going to use a VESC to drive the motor, and a 12 s 20 Ah Lipo battery to power everything. Next step is to mount a box to contain the batteries on the go-kart and then start working on the wiring to run via remote control. For this I don’t even need a micro controller - the steering servo and VESC can both work with normal RC pwm signals. Stay tuned, I will blog more about this in the future.

As if that project was not ambitious enough, I have another actual autonomous mower project I’m going to work on now as well. This is aimed at mowing yards, where the riding mower project is for larger spaces. For this I’m going to convert a push mower into an autonomous mower. I’ve decided to convert an electric mower so I don’t have to worry about gasoline; it can run whenever and charge on its own. Here you can see my preliminary work on this.

Converting an Electric Mower

The front wheels were replaced with omni-wheels so they rotate easily.

Mower Motor Replacement

I replaced the back wheels with two DC gear motors for differential steering.

Updating the Mower Wiring

The existing wiring was removed, and the battery compartment was opened up for easier access. Look at all that space! There was a 3-pound sand bag in the front so the mower didn’t tip backward.

My next steps are to figure out the power system and get the rear wheels made or purchased, then work on the rest of the electronics required to make it remote control. Autonomous conversion will happen after testing with just RC control.

Stay tuned to how these and other projects evolve. Thanks again for following along in my adventures!


As a thank you for reading this far, I would like to let you know I have a special promo code you can use to get 10% off any SparkFun Original products. Just use ORIGINALRED2020 during checkout. This code is good through the end of 2020, but can only be used once per customer. Thanks for reading - I hope I can start attending STEM shows next year and show off my hard work on these projects and others I have been working on.

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The Raspberry Pi 400 is Here!

via SparkFun: Commerce Blog

Hello everyone! As you may have seen from the title of today's blog, we are back again to announce another brand new Raspberry Pi product and you can order it from SparkFun, today. Please say hello to the Raspberry Pi 400, an affordable personal computer for day-to-day use! Two separate versions of this new computer are now available for preorder, a $70 stand-alone keyboard computer and a $100 kit that includes everything you need to get started except for a monitor! These new RPi's are a great way to work from home and study in today's world.

Raspberry Pi 400 Personal Computer Kit

Raspberry Pi 400 Personal Computer Kit

KIT-17377
$100.00
Raspberry Pi 400 Personal Computer (Unit Only)

Raspberry Pi 400 Personal Computer (Unit Only)

DEV-17376
$70.00

The Raspberry Pi 400 is a complete Raspberry Pi 4-based personal computer, integrated into a keyboard. By incorporating the board into a keyboard, it removes the need for a case and other accessories normally needed to run a Raspberry and creates a more clean configuration. It makes for the perfect configuration for a public machine or in an educational setting including the incorporation of a Kensington lock.

The Raspberry Pi 400 features a Broadcom 1.8GHz quad-core ARM Cortex-A72 CPU with 4GB of DDR4 RAM. VideoCore VI graphics (OpenGL ES 3.1, Vulkan) and 4kp60 HEVC decode provide the ability to run a 4k monitor at 60FPS or 2x 4k monitors at 30FPS through the two micro HDMI ports. An Ethernet port provides true Gigabit Ethernet support and there's two USB 3.0 and 1 USB 2.0 ports available for accessories and HIDs. A USB-C port is used for power and supports 5V, 3A operation. Finally the standard Raspberry Pi 40 pin connector is present on the back of the keyboard for HAT support.


SparkFun is very excited to carry the new Raspberry Pi 400. These new personal computers, built into compact keyboards, are a perfect place to get started with Raspberry Pi whether you are an experienced user, a new student, or anything in between. We expect to start shipping the Raspberry Pi 400 within the next week or two so make sure to place your order now to reserve your own!

Never miss a new product!

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Goodbye, October! Hello, Custom Board Designs.

via SparkFun: Commerce Blog

It has been a busy couple of weeks for us here at SparkFun. Last week we released the MicroMod line, which allows you easily swap out a variety of processors into function-specific carrier boards. This week we announced À La Carte (ALC), SparkFun's custom printed circuit board production service! We went into some detail about ALC on Wednesday, but we're excited so we're going to talk about it again, as well as a new SparkX product!

What can YOU make with ALC?

ALC helps you create new, custom boards

SparkFun has been designing boards for more than a decade, and we're the source for the latest and greatest technologies. We've taken all that knowledge built a platform that turns components and modules into easy-to-choose blocks. SparkFun À La Carte allows you to create custom boards by selecting only the blocks you want to use and adding them to your board. Whether you're a test engineer building 15 test fixtures or a Burning Man artist needing 47 light-activated servo controllers, ALC is there to bridge the gap between prototype and production.

Interested in trying ALC? We’re offering 50% off the design fee on all new orders through 11:59 p.m. on 12/31/2020 with promo code: ALCSPARKFUN50

Start your design with ALC


Qwiic Digital Capacitor - NCD2400M

Qwiic Digital Capacitor - NCD2400M

SPX-17182
$7.95

Ever need to fine tune an oscillator circuit or RF filter? It can be tricky and repetitive switching out capacitors on a PCB. SparkX's Qwiic Digital Capacitor, complete with the NCD2400M IC, can be a great solution. Solder the nibs onto any 0603 or 0402 footprint, plug in a Qwiic cable and RedBoard, and change the capacitance in code.


That's it for this week! As always, we can't wait to see what you make! Shoot us a tweet @sparkfun, or let us know on Instagram or Facebook. We’d love to see what projects you’ve made!

Never miss a new product!

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Mighty Modular Power Processors

via SparkFun: Commerce Blog

Hello there, everyone! We have had a very busy week here with two major product releases: On Monday, Raspberry Pi released their new Compute Module 4 series and, since we are now an Approved Reseller, we are offering several different options of the board including a way to easily access them. On Wednesday, we announced our brand new SparkFun MicroMod ecosystem that allows you to swap out small Processor Boards on function-specific Carrier Boards. Let's take a closer look!

Watch Avra build a project with our new MicroMod boards!

SparkFun MicroMod Artemis Processor

SparkFun MicroMod Artemis Processor

DEV-16401
$14.95
SparkFun MicroMod ESP32 Processor

SparkFun MicroMod ESP32 Processor

WRL-16781
$14.95
SparkFun MicroMod SAMD51 Processor

SparkFun MicroMod SAMD51 Processor

DEV-16791
$14.95

Pick processors from SparkFun's own Artemis to ESP32 or SAMD51 (and more to come). Mix, match, test and prototype different processors with few to no code changes!

  • SparkFun MicroMod Artemis Processor: Leveraging the ultra powerful Artemis Module, the SparkFun MicroMod Artemis Processor is the brain board of your dreams. With a Cortex-M4F with BLE 5.0 running up to 96MHz, and with as low power as 6uA per MHz (less than 5mW), the M.2 MicroMod connector allows you to plug in a MicroMod carrier board with any number of peripherals.
  • SparkFun MicroMod ESP32 Processor: The MicroMod ESP32 Processor Board combines Espressif's ESP32 with our M.2 connector interface to bring a processor board with reliable WiFi and Bluetooth capabilities into our MicroMod ecosystem.
  • SparkFun MicroMod SAMD51 Processor: With a 32-bit ARM Cortex-M4F MCU, the SparkFun MicroMod SAMD51 Processor Board is one powerful microcontroller packaged on a small board! The provides you with an economical and easy-to-use development platform if you need more power with minimal working space.

Rob goes over the MicroMod ecosystem boards in more detail!

SparkFun MicroMod ATP Carrier Board

SparkFun MicroMod ATP Carrier Board

DEV-16885
$19.95
SparkFun MicroMod Input and Display Carrier Board

SparkFun MicroMod Input and Display Carrier Board

DEV-16985
$59.95
SparkFun MicroMod Data Logging Carrier Board

SparkFun MicroMod Data Logging Carrier Board

DEV-16829
$19.95
SparkFun MicroMod Machine Learning Carrier Board

SparkFun MicroMod Machine Learning Carrier Board

DEV-16400
$19.95

Choose a carrier board to access different inputs and outputs based on your specific needs. Each carrier board is easily expandable by utilizing our Qwiic Connect System.

  • SparkFun MicroMod ATP Carrier Board: Access all the pins (i.e. ATP) of the MicroMod processor boards with the SparkFun MicroMod ATP Carrier Board! This board breaks out the MicroMod processor board's pins on the M.2 connector to 0.1-inch spaced female headers and PTH pads on the edge of the board.
  • SparkFun MicroMod Input and Display Carrier Board: This carrier board combines a 2.4-inch TFT display, six addressable LEDs, onboard voltage regulator, a 6-pin IO connector, and microSD slot with the M.2 pin connector slot, so it can be used with compatible processor boards in our MicroMod ecosystem.
  • SparkFun MicroMod Data Logging Carrier Board: The SparkFun MicroMod Data Logging Board offers a highly customizable, low-power data logging platform using the MicroMod system, allowing you to choose your own processor to pair with the carrier board.
  • SparkFun MicroMod Machine Learning Carrier Board:The MicroMod Machine Learning Carrier Board combines some of the features of our SparkFun Edge Board and SparkFun Artemis boards, but allows you the freedom to explore with any processor in the MicroMod lineup without the need for a central computer or web connection. Voice recognition, always-on voice commands, gesture, or image recognition are possible with TensorFlow applications.

Raspberry Pi Compute Module 4 32GB (Wireless Version) - 4GB RAM

Raspberry Pi Compute Module 4 32GB (Wireless Version) - 4GB RAM

DEV-17392
$65.00
Raspberry Pi Compute Module 4 Lite (Wireless Version) - 2GB RAM

Raspberry Pi Compute Module 4 Lite (Wireless Version) - 2GB RAM

DEV-17384
$30.00
Raspberry Pi Compute Module 4 8GB - 2GB RAM

Raspberry Pi Compute Module 4 8GB - 2GB RAM

DEV-17284
$35.00
Raspberry Pi Compute Module 4 8GB (Wireless Version) - 2GB RAM

Raspberry Pi Compute Module 4 8GB (Wireless Version) - 2GB RAM

DEV-17391
$40.00
Raspberry Pi Compute Module 4 16GB - 2GB RAM

Raspberry Pi Compute Module 4 16GB - 2GB RAM

DEV-17390
$40.00
Raspberry Pi Compute Module 4 - Lite

Raspberry Pi Compute Module 4 - Lite

DEV-17364
$25.00
Raspberry Pi Compute Module 4 I/O Board

Raspberry Pi Compute Module 4 I/O Board

DEV-17360
$35.00
Raspberry Pi 4 Compute Module Antenna Kit

Raspberry Pi 4 Compute Module Antenna Kit

WRL-17389
$5.00

Since we are now an Approved Reseller for Raspberry Pi, we are happy to carry versions of the brand new Raspberry Pi Compute Module 4. The Raspberry Pi Compute Module 4 represents a huge change for the Compute Module line, the biggest change being the move from the DDR2 SODIMM connector form factor to a high density connector on the bottom of the board. True to the line, the Compute Module 4 packs all the best features of the Raspberry Pi Model B 4 into a more favorable form-factor for embedded or OEM applications.


That's it for this week! As always, we can't wait to see what you make! Shoot us a tweet @sparkfun, or let us know on Instagram or Facebook. We’d love to see what projects you’ve made!

Never miss a new product!

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Introducing SparkFun MicroMod

via SparkFun: Commerce Blog

Today is a special day for us - for the last several months we've been working on a new and growing ecosystem of products that customize the processor you want to use. Meet MicroMod, a modular interface ecosystem that connects a microcontroller “processor board” to various “carrier board” peripherals utilizing the M.2 standard.

MicroMod

As a modular ecosystem of interchangeable processors and carrier boards, MicroMod enables rapid prototyping and development that allows for dynamic project changes. There's no need to worry about soldering or finding the right length cable - just swap your processor and go! Whether you are an avid electronics enthusiast or a professional engineer, the MicroMod system works to make project and prototype upgrades as seamless as possible.

Now let's meet the boards!


Carrier Boards: These provide access to different peripherals and functionality.

SparkFun MicroMod ATP Carrier Board

SparkFun MicroMod ATP Carrier Board

DEV-16885
$19.95
SparkFun MicroMod Input and Display Carrier Board

SparkFun MicroMod Input and Display Carrier Board

DEV-16985
$59.95
SparkFun MicroMod Data Logging Carrier Board

SparkFun MicroMod Data Logging Carrier Board

DEV-16829
$19.95
SparkFun MicroMod Machine Learning Carrier Board

SparkFun MicroMod Machine Learning Carrier Board

DEV-16400
$19.95

Choose a carrier board to access different inputs and outputs based on your specific needs. Each carrier board is easily expandable by utilizing our Qwiic Connect System.

  • SparkFun MicroMod ATP Carrier Board: Access all the pins (i.e. ATP) of the MicroMod processor boards with the SparkFun MicroMod ATP Carrier Board! This board breaks out the MicroMod processor board's pins on the M.2 connector to 0.1" spaced female headers and PTH pads on the edge of the board.
  • SparkFun MicroMod Input and Display Carrier Board: This carrier board combines a 2.4" TFT display, six addressable LEDs, onboard voltage regulator, a 6-pin IO connector, and microSD slot with the M.2 pin connector slot, so it can be used with compatible processor boards in our MicroMod ecosystem.
  • SparkFun MicroMod Data Logging Carrier Board: The SparkFun MicroMod Data Logging Board offers a highly customizable, low-power data logging platform using the MicroMod system, allowing you to choose your own processor to pair with the carrier board.
  • SparkFun MicroMod Machine Learning Carrier Board:The MicroMod Machine Learning Carrier Board combines some of the features of our SparkFun Edge Board and SparkFun Artemis boards, but allows you the freedom to explore with any processor in the MicroMod lineup without the need for a central computer or web connection. Voice recognition, always-on voice commands, gesture, or image recognition are possible with TensorFlow applications.

Processor Boards: Mix and match processor boards and choose which one works best for you.

SparkFun MicroMod Artemis Processor

SparkFun MicroMod Artemis Processor

DEV-16401
$14.95
SparkFun MicroMod ESP32 Processor

SparkFun MicroMod ESP32 Processor

WRL-16781
$14.95
SparkFun MicroMod SAMD51 Processor

SparkFun MicroMod SAMD51 Processor

DEV-16791
$14.95

Pick processors from SparkFun's own Artemis to ESP32 or SAMD51 (and more to come). Mix, match, test and prototype different processors with little to no code changes!

  • SparkFun MicroMod Artemis Processor: Leveraging the ultra powerful Artemis Module, the SparkFun MicroMod Artemis Processor is the brain board of your dreams. With a Cortex-M4F with BLE 5.0 running up to 96MHz, and with as low power as 6uA per MHz (less than 5mW), the M.2 MicroMod connector allows you to plug in a MicroMod carrier board with any number of peripherals.
  • SparkFun MicroMod ESP32 Processor: The MicroMod ESP32 Processor Board combines Espressif's ESP32 with our M.2 connector interface to bring a processor board with reliable WiFi and Bluetooth capabilities into our MicroMod ecosystem.
  • SparkFun MicroMod SAMD51 Processor: With a 32-bit ARM Cortex-M4F MCU, the SparkFun MicroMod SAMD51 Processor Board is one powerful microcontroller packaged on a small board! The provides you with an economical and easy-to-use development platform if you need more power with minimal working space.

Guides and Resources: Find the guide that's right for you.

Make your own MicroMod processor and carrier boards utilizing SparkFun’s Eagle libraries and guides. We have multiple open source carrier boards already designed so you can use them as a reference design and starting point. We can’t wait to see what you make.

New!

Getting Started with MicroMod

October 21, 2020

Dive into the world of MicroMod - a compact interface to connect a microcontroller to various peripherals via the M.2 Connector!
New!

Designing with MicroMod

October 21, 2020

This tutorial will walk you through the specs of the MicroMod processor and carrier board as well as the basics of incorporating the MicroMod form factor into your own PCB designs!

We are incredibly proud of this release, and we have plenty more ideas to grow MicroMod into a system of multiple processors and carriers that provide you with all the combinations of boards you can imagine. We'll look deeper into each board this Friday when Avra brings you a project showing the boards in action! See you then!

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