[carpe] meeting planning: Soldering project // TDD USB _controlled_ 'traffic light'

[R P Herrold]

I found my (rather over-engineered) ThinkM 'block' v.2 device 
... I think I probably supported their Kickstarter for the 
initial one

The packaging notes they have set up an 'IFTTT'  control 
instance at:
	http://ifttt.com/blink1/

with 'free' starter accounts
	

There are ready built 'transiently displayed' status message 
tools for X-tops [1], and OS/X .. and one assumes MSFT kit, 
that move onto, linger, and then self-hide after a 
configurable timeout

The various windowing tool kits tend to add this as well

[herrold at centos-7 ~]$ rpm -qa \*dialog\*
python2-dialog-3.3.0-6.el7.noarch
dialog-1.2-4.20130523.el7.x86_64


Wrapping a go / nogo TDD tool to poke a script, which in 
turns:
	1. pokes IFTTT to toggle state
	2. display that message

seems trivial.  We can breadboard such together with an 
ESP8266 or ESP32, and be most of the way home [2] plus ( [3] 
[4] ) -or- [5] for under $20, and have nice storage cases and 
much 'junk box' bait left over.  My 'BangGood' fu is failing 
me a bit on finding a multi-color LED, and nice boxed set of 
resistor assortment.  There is a possible 15 pct coupon as 
well: DIYSCM


Designing a PCB for discrete components, using an USB plug and 
either take a variable color led, or three -- R Y G -- leds as 
a soldering project comes to mind.  For doing the copper 
etching, drilling, silkscreen and such OSH park seems to have 
a good reputation [6]


We need to decide if it 'plugs into' the USB port directly, or 
uses a micro / mini cable, and has a 'header' on the PCB; also 
socketed or no for the ESP, and single or multiple LED 
drivers, and of course current limiting resistors to protect 
the magic smoke.  Perhaps local power conditioning and an 
over-voltage 'crowbar' protector. I sort of forget if current 
limited Darlington pair components <?> exist

-- Russ

1. xmessage -timeout 10 "broken build" &

[herrold at centos-7 ~]$ rpm -qf `which xmessage`
xorg-x11-apps-7.7-7.el7.x86_64


2. Wemos® Lolin ESP32 OLED Module For Arduino ESP32 OLED WiFi 
+ Bluetooth Dual ESP-32 ESP-32S ESP8266 OLED Module $  10.49 
or $ 12.20 ... use the .cn whse for less expensive

3. Geekcreit® 375pcs 3MM 5MM LED Light Emitting Diode Beads 
Resistance Lights Kits Bulb Lamp -- $ 4.26

https://www.banggood.com/375pcs-3MM-5MM-LED-Light-emitting-Diode-Beads-Resistance-Lights-Kits-Bulb-Lamp-p-1027601.html?rmmds=search

4. Geekcreit® MB-102 MB102 Solderless Breadboard + Power 
Supply + Jumper Cable Kits Dupont Wire For Arduino -- $ 6.11

https://www.banggood.com/MB-102-MB102-Solderless-Breadboard-Power-Supply-Jumper-Cable-Kits-Dupont-Wire-For-Arduino-p-933600.html?rmmds=detail-top-buytogether-auto

5. Geekcreit® Portable Components Starter Kit For Arduino 
Resistor / LED / Capacitor / Jumper Wire / 400 Hole Breadboard 
/ Resistor Kit With Plastic Box $ 7.15

https://www.banggood.com/Geekcreit-Components-Starter-Kit-For-Arduino-Resistor-LED-Capacitor-Jumper-Wire-Breadboard-p-1165713.html?rmmds=search&cur_warehouse=CN

6. https://oshpark.com/