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ถูกปรับปรุง 22 hours 55 min ก่อน

MAKERVILLA 3.0

พุธ, 07/17/2019 - 19:00

MAKERVILLA is back! It will be held 31 July – 2 August 2019 at the National Design Centre Singapore.

MAKERVILLA 3.0 is a 3-day creative learning experience (CLX) design conference for local and international makers, practitioners & educators to gather under one roof for a time of learning, dreaming, hacking and sharing of ideas.

Find out more on their website at makervilla.com.  Mark your calendar!

#FreePCB via Twitter to 2 random RTs

พุธ, 07/17/2019 - 06:06

Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week:

  • Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

Spectrometer on PC

พุธ, 07/17/2019 - 06:05

Boris Landoni over at Open Electronics writes, “We use the platform based on the AMS sensors in combination with the Personal Computer and thanks to an ad hoc software we trace on the screen the spectrum curves resulting from the analysis performed.”

More info on Open Source Project page.

6CY7 dual triode valve amplifier

อังคาร, 07/16/2019 - 06:50

Josh built this 6CY7 dual triode valve amplifier:

I’ve always wanted to know what the “tube magic” was all about. There is much opinion in the science of music production, probably because music and its perception is highly personal and subjective. Ive always imagined that since transistor amplifiers were “perfect” with their large amounts of negative feedback, great linearity, and low THD that tube amplifiers must add something to sound that generates their appeal. From the reading I’ve done it has to do with harmonics.

More details on imsolidstate blog.

App note: Programmable analog functions

จันทร์, 07/15/2019 - 00:00

Another app note from ON Semiconductors about various digital potentiometers application. Link here (PDF)

Analog circuits are made programmable by using digital potentiometers (POTs) to vary the key circuit parameters. This application note provides the analog design engineer with basic reference designs and circuit ideas for controlling the key parameters of analog circuits using digital POTs connected to a computer bus or microcontroller. Analog circuits are made programmable by using digital potentiometers (POTs) to vary the key circuit parameters. This application note provides the analog design engineer with basic reference designs and circuit ideas for controlling the key parameters of analog circuits using digital POTs connected to a computer bus or microcontroller.

App note: Digital potentiometer (POT) to control LED brightness

อาทิตย์, 07/14/2019 - 21:00

Controlling LED brightness through digital potentiometer and a LED driver from ON Semiconductor. Link here (PDF)

Light-emitting diodes (LEDs) require a regulated current, and their brightness is proportional to the current that flows through them. Some LED drivers use an external resistor to set the LED current. A digital POT can replace a discrete resistor with the advantage of providing an adjustable value allowing the LED brightness to dynamically change. Most digital POT circuits have the ability to store permanently the resistor value in non-volatile memory.

Run a Korg SQ-1 Sequencer from a 9V Stompbox supply

ศุกร์, 07/12/2019 - 06:46

 

Run a Korg SQ-1 Sequencer from a 9V Stompbox supply:

The Korg SQ-1 is a great little sequencer, and one of my favourite bits of kit for its simple hands-on feel and penchant for lucky randomness (I have 3 of them!)
I tend to use it in a live setup with no computer but with a lot of guitar effect pedals on 9V daisy chain cables. The fact that the SQ-1 can only use batteries or USB power becomes a bit annoying so I decided to hack one so it can run on the same power supply as the pedals.

More details on Stuff and Nonsense blog.

Simple NTP clock using USB display module

ศุกร์, 07/12/2019 - 06:31

Dilshan Jayakody writes:

Simple NTP clock is a maintenance-free clock application developed to work on single-board computers like Raspberry Pi, Orange Pi, etc. This clock application uses the Simple Network Time Protocol (SNTP) to get the time and display it on seven segment display which I designed.  This application is designed to work on most of the Linux based systems and had minimum dependencies with system libraries and peripherals. I developed this application to work with Allwinner H2 Plus based Orange Pi Zero board, but this can compile for other platforms without doing any modifications on the source code.

See the full post on his blog.

#FreePCB via Twitter to 2 random RTs

พุธ, 07/10/2019 - 04:00

Every Tuesday we give away two coupons for the free PCB drawer via Twitter. This post was announced on Twitter, and in 24 hours we’ll send coupon codes to two random retweeters. Don’t forget there’s free PCBs three times a every week:

  • Hate Twitter and Facebook? Free PCB Sunday is the classic PCB giveaway. Catch it every Sunday, right here on the blog
  • Tweet-a-PCB Tuesday. Follow us and get boards in 144 characters or less
  • Facebook PCB Friday. Free PCBs will be your friend for the weekend

Some stuff:

  • Yes, we’ll mail it anywhere in the world!
  • Check out how we mail PCBs worldwide video.
  • We’ll contact you via Twitter with a coupon code for the PCB drawer.
  • Limit one PCB per address per month please.
  • Like everything else on this site, PCBs are offered without warranty.

We try to stagger free PCB posts so every time zone has a chance to participate, but the best way to see it first is to subscribe to the RSS feed, follow us on Twitter, or like us on Facebook.

Bitcoin mining on an Apollo Guidance Computer: 10.3 seconds per hash

อังคาร, 07/09/2019 - 23:37

Ken Shirriff implemented the SHA-256 hash algorithm and ran it on the vintage Apollo Guidance Computer (AGC) that they’re restoring:

We’ve been restoring an Apollo Guidance Computer. Now that we have the world’s only working AGC, I decided to write some code for it. Trying to mine Bitcoin on this 1960s computer seemed both pointless and anachronistic, so I had to give it a shot. Implementing the Bitcoin hash algorithm in assembly code on this 15-bit computer was challenging, but I got it to work. Unfortunately, the computer is so slow that it would take about a billion times the age of the universe to successfully mine a Bitcoin block.

See the full post on Ken Shirriff’s blog.

‘No-Parts’ temperature measurement with Arduino Pro Mini

จันทร์, 07/08/2019 - 21:47

From the comments on our ESP8266 temperature logger post, Edward Mallon  writes:

The ESP8266 has a hardware watchdog timer, so you could probably use that to measure temperature to much better resolution that you’d get from a DS18B20. We get better than 0.003C using the technique with cheap Pro Mini Clones
Ooops, I missed an important aspect of the two clock method – the inter-reading jitter in the micros() reads brings the resolution down to DS18b20 levels.

More details on Underwater Arduino Data Loggers blog.

App note: High density serial flash addressing

จันทร์, 07/08/2019 - 00:55

Old app note from Macronix about accessing high density serial flash. Link here (PDF)

Many consumer products have converted or are converting from parallel flash to SPI serial flash. Generally, high end applications require higher memory density, but in the past, serial flash densities were limited to 128Mb due to addressing constraints.

App note: USB On-The-Go (OTG) basics

อาทิตย์, 07/07/2019 - 20:00

USB OTG explained in this app note from Cypress Semiconductors. Link here

This application note discusses several aspects of OTG functionality. The note introduces end-applications and different types of cables and connectors involved with OTG. It also describes the OTG protocol state changes when both Mini-A and Mini-B devices are connected .The host negotiation protocol (HNP) and session request protocol (SRP), which are part of the OTG protocol, are also explained.

Acorn BBC Master and electron cartridge breakout

ศุกร์, 07/05/2019 - 21:19

The Acorn Master cartridge breakout board by Simon Inns:

This project provides a simple breadboard adapter/breakout board for prototyping cartridges for the Acorn BBC Master and Acorn Electron 8-bit computers.
The design consists of two PCBs, the first plugs into the computer’s cartridge slot and the second is designed to plug along the edge of a standard 2.54mm pitch breadboard.  The two boards are connected by a length of 50-way ribbon cable.

Project info at waitingforfriday.com and GitHub repository here.

USB seven segment display module

ศุกร์, 07/05/2019 - 06:41

Dilshan Jayakody published a new build:

This project is about an open source, USB based, 10 digit seven segment display unit. This unit is specifically designed to work with POS systems and banking applications. Initially, this system is developed to work with PC based systems, and later it was modified to work with other platforms and applications.

See the full post on his blog.

Use a MCP4728 DAC with AVR ATmega

พฤ, 07/04/2019 - 06:58

AVR ATmega MCP4728 DAC library:

The MCP4728 device is a quad channel, 12bit voltage output DAC. It also has EEPROM embedded. The DAC is driven using the I2C interface.
This library implements an ATmega driver for this IC.

More details on Davide Gironi’s blog.

Check out the video after the break.

Build your own IoT/MQTT node for less than $2

พฤ, 07/04/2019 - 06:39

Albert David writes, “This blog explains how to use ESP-12F module without the need of a base board but with minimal set of components.”

See the full post on his blog.

Making a SPL dB meter

จันทร์, 07/01/2019 - 21:22

Shawon Shahryiar over at Embedded Lab shared a how-to on making a SPL dB meter:

Sound needs a medium for propagation or travel. It can’t travel in vacuum. Normally air is that medium but sound can also propagate in liquids and other states of matter. I am not going to lecture on how sound travels and its properties as Wikipedia details everything well here. Everything we see around us has a measurement and a unit. In case of sound pressure, the unit is decibel. Our basic requirement is to be able to measure Sound Pressure Level (SPL) in decibel scale with a typical 8-bit microcontroller, an ordinary microphone and without involving complex algorithms.
Measurement of sound has a number of uses. For instance, monitoring sound pollution, security system, monitoring the quality of an amplifier, detecting sound profile of an environment, etc.

App note: Meeting transient specifications for electrical systems in military vehicles

อาทิตย์, 06/30/2019 - 20:50

Hardened circuit protection against voltage spikes and surges tackled in this app note from Vicor. Link here (PDF)

Electrical systems in military vehicles are normally required to meet stringent transient requirements. Typical of these specifications is the MIL-STD-1275B. Although the specified levels of these surges and spikes are outside the capability of Vicors Maxi, Mini, Micro Series modules, it is quite possible, with simple circuitry, to make the 24V input (18 – 36V input range) DC-DC converter modules compliant to these specifications for the 28V vehicle voltage system. Other electro-magnetic compatibility requirements, such as MIL-STD-461E and/or DEF-STAN 59-41, apply to military vehicles, but these are outside the scope of this application note. In order to meet additional conducted emission requirements an input filter, preceding the transient protection circuit covered in this application note, will be required.

3 cent PMS150C MCU driving 300 WS2812B LED’s

พุธ, 06/26/2019 - 06:50

Driving 300 WS2812B RGB LED’s with “the 3 cent microcontroller” – the Padauk PMS150C.

The 3 cent Padauk PMS150C is.. Interesting to say the least. First of all there’s a lot this little MCU doesn’t do. It doesn’t have a lot of code space (1K Word), it doesn’t have a lot of RAM (64 bytes) and it doesn’t even do hardware multiplication. It doesn’t have an instruction for loading data from ROM either(Though there are ways of getting around this – but that’s a subject for another post). And of course – you can only program it ONCE.

More details at ABNielsen.com.

Check out the video after the break.