Arduino LED "Roto" Clock and other Arduino Projects

[mediatechnology]

Well it finally had to happen. Wayne modified and wrote some code.

The Arduino LED "Roto" Analog Clock:



I will be adding switches and code for time-setting and may add WiFi Net time synchronization.
The display is single-wire data using WSM2812 addressable RGB LEDs.
The clock runs on an Arduino Nano ATMega328.

The time is 10:58:54.


A broadcast countdown clock is also in the works.

I've also done a simple H-bridge stepper controller for a friend's project.
All it does is run a 50:1 gear-reduced 15° stepper at 3 RPM output shaft speed.
The stepper fits in an Arduino Nano ATMega168.



The USB on these boards are not the standard FTDI232 but the lower-cost CH340.
The Arduino IDE is not supplied with CH340 drivers which must be downloaded here: http://www.wch.cn/download/CH341SER_EXE.html

[JR.]

oh-oh... welcome to the dark side...

JR

[mediatechnology]

I stay up late to code. Becoming a real night owl.

The stepper was an epic fail due to vibration. I suspected that when I ran it.
It wasn't the cogging, since it was geared, but internal clacking each time it stepped.
Too much vibration damping/shock mounting would be required.

We need a silent-running low RPM synchronous motor and they work quite well except for heat and 120/240 adaptation.
The client has been using a rotisserie motor and other than having to separately stock 120/240 they work well.
The 50/60Hz discrepancy isn't a factor.

I found some really cool brushless DC low RPM motors with gear boxes that are relatively flat.
They have the controller on-board and can be slowed, if needed, by external PWM.

It's back to the clock code to set the time.
No one bothers me at midnight.

[JR.]

My ability to code has deteriorated over the years, not some single observable cognitive deterioration, but the requirement to hold so much related stuff in front of mind for easy access.

Back when I was still jogging I would work on difficult coding problems in my head while running 5 miles. Not detailed code work but obscure coding architecture or algorithm design. I could also come up with some solutions overnight apparently while sleeping. I used to call that my overnight engineering team.

Now I can have a hard time just figuring out code that I wrote myself, but some of that is because of sloppy documentation. Many thousands of lines of code in my drum tuner.

That said I can still have trouble reading some of my old electronic circuit schematics (like the TS-1), but they could be difficult to grok even before I got old.

JR

[mediatechnology]

I finally got tired of the 5 seconds per day drift of the DS1307 RTC with this clock and tried out a DS3231 RTC module.

The DS3231 TCXO has a 0-40°C time base error of only ±2 ppm vs the almost 60 ppm error of the DS1307's external crystal.

I think I paid about $2.50 US for the DS3231 module.

Its I2C interface is identical and works with the Arduino RTClib.h library.
Other than declaring the rtc to be a DS3231 I had to change one line of code which tests to see if the clock has been initially set.

After 36 hours running in an unheated garage on an outside uninsulated wall I can't perceive any drift.
The $2.50 was well worth it and the accuracy is now as good as an $8.95 AA-battery-powered analog wall clock.

[JR.]

my fancy outdoor thermometer (weather forecaster) has a radio updated time standard. Not that web connected computers are not accurate.

My fancy weather forecaster that always says it is going to rain, this week said it was going to snow.... still wrong about the weather but at least the thermometer works.

JR

[mediatechnology]

I've been using my "Atomic" clocks sync'd to WWVB to check the new RTC.
I also use https://time.is and WWV's dial-up audio at 303-499-7111.

[terkio]

The DS3231 TCXO has a 0-40°C time base error of only ±2 ppm vs the almost 60 ppm error of the DS1307's external crystal.

I think I paid about $2.50 US for the DS3231 module.

Is the DS3231 a module or an IC ?
Is the Xtal integrated inside the IC ?

[mediatechnology]

The DS3231 is an IC with an internal TCXO crystal.
I'm using a board with an on-board AT24C32 EEPROM like these: https://www.ebay.com/sch/i.html?_from=R ... o&_sacat=0

[terkio]

This clock accuracy, 2 ppm, is pretty amazing at this low cost $2.50.
I presumed integrating a crystal had a substantial cost. Not so, this looks like magic to me.
Other IC you might be interested in.
Audio player.
MP3 decoder chip.
http://www.flyrontech.com/eproducts/164.html
MP3 modules.
http://www.flyrontech.com/eproducts/?id=10