T3 BaseBoard - organized modular connection system for the Teensy 3.

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t3andy

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T3_BB_r1.jpg

"The Teensy 3 is just only an Arduino software compatible carrier 32 bit ARM stamp using the Freescale ARM M4 K20" --> Thanks Paul S.
Having PWM, touch, hardware serial 1-3, SPI, I2C, analogs and digitals needs a solution to sort out all the I/O
into a organized, modular, solid connection system. This is where the T3 BaseBoard comes into play.

My next door neighbor, the PCB designer, designed the T3 BaseBoard, for my Teensy 3, on very short notice. He designed a modular
connection system to deploy the Teensy 3 for rapid software, hardware testing and design.

The T3 BaseBoard is only a prototype and no expense was spared.
This board was not made for commercial applications but through a little reverse
engineering of the PCB layout pattern it could be easily duplicated.
You could also order the exact board through the same PCB prototype house but the
cost would be prohibitive unless the order quantity of units are increased substantially.
Maybe a large forum group user "at cost" purchasing would reduce the unit cost down substantially.

T3 BaseBoard Features:

Twenty seven, four pin, modular, JST (Japan Solderless Terminals)
two mm. connectors are used for the Teensy 3 I/O. (includes +3.3 VDC power and ground)
The 4 pin modular format is the same throughout with minor exceptions.
This same 4 pin modular pin-out format is incidentally exactly compatible with SeeedStudio's
low cost Grove electronic widgets.

Current limits (620 ohm resistors) protects all Teensy I/O pins from over-current, direct shorts,
pin to pin shorts or mis-wired I/O connections.

On-board 1 A 3.3 VDC LDO regulator is used for additional Teensy 3 power.
Needs an external +5 VDC +- 5 % regulated power supply input.

Two on-grid ( 0.1 space) 14 pin header stacking sips (1.6” on-grid apart) for Teensy 3 breadboard testing.

Two on-grid ( 0.1 space) 14 pin header header sips also for Teensy 3 breadboard testing.

On-board special Teensy 3 power and signal protection designed to keep the Teensy 3 healthy and from user destruction.

Three hardware serial I/O ports on separate JST modular connectors. (with power and ground)(Serial 1-3)

Three separate SPI bus I/O on modular JST 2 mm connectors with chip selects. (SPI 1-3)

Four individual I2C bus on JST modular connectors. (with power and ground and optional bus pullups)

Six, quick connect, on-board, low power, 3 mm LEDS with dropping resistors for user status testing.

A complex but flexible on-board power setup configuration with many user power options.

Eight analogs on four JST modular connectors using the Teensy 3 provided clean "analog ground".

Please note: Due to the PCB prototype house board size limitations, none of the Teensy 3 bottom I/O was
included on the T3 BaseBoard.


Any comments welcomed for improving the T3 BaseBoard.
BTW ... See attached pdf pic for the T3 BaseBoard
 

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Added a picture of L2 (bottom layer) of the Teensy 3 BaseBoard.
Notice the optional shorting bars to disable the current limit resistors.
The heavy duty 3.3 VDC 1A regulator and heat sink is "exposed" on the bottom of the T3 Baseboard.
Notice the current limit SMT which protects the Teensy 3 from over current in the standalone power mode.
 

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ExpressPCB charges $85.80 USD for 3 mini-boards (includes shipping) but the price drops to $5.97 per board @ quantity 100.

The approximate cost for the parts for the T3 Baseboard is about $13 USD.

The key to this T3 BaseBoard design is NOT buying the JST connectors from Digi-key but from SeeedStudio @ 10 cents a piece.
You might have to wait for about 15 days of FREE shipping from SeeedStudio but it is well worth it.
Most US based electronic distributors make their money on connectors in which they charge sky high prices.

As for assembly, this board was created to allow the end user to construct this board in a kit form. Having to solder the SMT 0805's resistors,
by hand, is a truly rewarding experience.
 
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Just wanted to show how easy it is to connect several devices to the T3 BaseBoard.
In the attached picture below ...

As you can see, without using an organized modular connection system on the T3 BaseBoard, you would be in a terrible wiring nightmare.

Bottom left is the Adafruit mirco SD card running sdFat library using SPI 1.
Notice that the micro SD SPI uses two patch cables. One cable is for CLK,SS,MOSI,MISO SPI bus signals and the other patch cable is just power and ground from one of the unused spares JST connectors. Using beta8, the micro SD only runs at SPI "half speed"?

Above the SD card breakout board is the Adafruit Ultimate GPS breakout connected to hardware serial1 running the tinyGPS NEMA "polling" library. Also connected to the GPS is an "active" power hungry antenna.

Both the SD and GPS easily consume more than the 100 ma. Teensy 3 on-module regulator provides. The T3 BaseBoard on-board 1A 3.3 VDC regulator provides the extra juice for these devices.

To the right of the T3 BaseBoard is the precision I2C DS3232 RTC using one connector on the I2C 4x bus. I had to bridge out the two I2C bus series 620 ohm current limit resistors to make the I2C bus to function.

All six status LEDs are connected via patch cables to the Teensy 3 digitals for user testing status.

By buying the inexpensive JST patch cables from SeeedStudio and cutting them in half to create end module connections is a way to save on patch cabling cost.

To my amazement all devices worked (software-wise Beta8) on the T3 BaseBoard with no software modifications! Something is being done right at pjrc.com!;)
 

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Here is the preliminary schematic for the T3 BaseBoard Modular I/O and Power ...
 

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SeeedStudio “Grove compatible” devices available to “plug and play” on the T3 BaseBoard.
http://www.seeedstudio.com/depot/
then search for “Grove”

The following is just a very small sampling of the Grove
low cost modules that could be plugged directly into the T3 Baseboard.

Please note: All SeeeDepot software libraries, code snippets and
hardware will need to be re-verified for Teensy 3.
Inspect and make sure all Grove devices are for +3.3 VDC operation before purchasing!

Grove - 3 - axis Digital Accelerometer ADXL345 I2C SKU: SEN04051P
Notes: I2C interface - software uses wire.h

Grove - 3-axis Compass SKU: SEN12753P I2C
Note: 3.3 VDC power - software uses wire.h.

Grove - 3-axis Gyro SKU: SEN11763P
Notes: 3 VDC interface - I2C (FAST) - software uses wire.h

Grove - I2C Color Sensor - SKU: SEN60256P
Notes: Uses 12C - software uses wire.h

Grove - 80cm Infrared Proximity Sensor SKU: SEN39046P
Notes: 2.5 V min. voltage, uses analog read and has a special 3 pin
to 4 pin JST Grove connector which has the same pin-out as the T3 BaseBoard.

Grove - Button(P), single LEDs, tilt switch, slide switch,
rotary angle sensor, LED bar, light sensor should work with no modifications.

BTW ... I don't work for SeeedStudio (China).;)
 
I cannot find T3 baseboard in main page of PJRC. I recommend you could using PCBA Turkey service from NexPCB.
It is very important verify the function of your design ASAP!
 
hmmm, smells like spam to me billatpjrc who isn't at PJRC at all.

If forum admins agree with me then I hope this post (mine) is deleted with his post if his post is deleted.

Edit: Yeah, clear use of keywords for link spam - if you see this Bill I strongly suggest you get professional SEO company for your website and don't spam forums, very unpopular stuff.
 
They have office in Boston too, pretty sure - not my problem with his post, it is link spam and *already* Google has noted this forum effectively endorsing their crap for now but WHEN his post (and, I hope all of ours mentioning it) has (/have) been deleted Google will note that as well and some simple software on their servers will notate it as link spam and negate (at least part of) their score in how they rank results in their searches.

I worked in SEO for a couple of years, boss claimed to be white hat but wasn't after all. I am sure that if I named him and his business his vindictiveness would quickly show and may even hurt me a bit - maybe he has given away lurking behind me in forums, even ages ago, but if something negative was said about his business I am sure he would find it quick enough.


This forum is an excellent target for link spammers because it does not advertise and many posts here should look like rich and juicy good stuff to the algorithms which can loosely be collectively known as GoogleBot.
 
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billatpjrc, you have one more message in the next 12 hours to say something non-spammy.

Have you actually used Teensy or Arduino?
 
To everyone, if you see spam, use the little black triangle to report it directly to Robin.

Every week she works unseen and unnoticed, deleting and banning spammers (they often wait, hoping to evade "new acct" filters), and she bans IP ranges when they try repeatedly. The silly playthru game mostly keeps the bots out, but several human spammers still get in....

If you see something that you're sure is spam, please report it. Because we have so little spam here, it may seem like nobody is watching, but really, the reason we have so little spam is due to Robin watching new user registrations.
 
(facepalm)

Sorry Paul, I looked and looked for the 'report' etc button and managed to blissfully ignore the little triangle - had I seen it I would not have made my post but instead hit that and entered why I think it is just evil spam in the textbox I expect I will find if I click one now.

I've the impression you posted after midnight your time and now posted before 6am your time - I hope you are getting enough sleep :)

@t3andy: unless you can find some humor, or other entertainment value, in any of it I apologise for my participation in probable detraction (and definite off topic) in your thread.
 
OK, I'm bringing down the hammer (just like Thor :D). When I ban users identified as spammers I delete everything that user has posted, but I don't delete the account right away. If I do ban someone by mistake (it's happened once or twice of the literally thousands of accounts I've banned), I can reactivate the account, but the posted messages that were deleted are gone forever.
 
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