Teensy 4.0 Breakout Kit

KurtE said:
Yep - been there... Actually mine is now probably damaged... hopefully it might still work, but it felt like the only realistic way I could solder both on in that space.
Think that is exactly why I may have fried my T4. Hopefully yours will still work. Also going to take @defragster advice for the next round - no flux under the flex cable.
 
@mjs513 - Will keep fingers crossed. Also will again first try washing with hot water and then dry first to hopefully remove as much flux residue as possible...
 
@loglow
I would expect a fresh battery to put out 3V? Perhaps you got a bad one? Please double-check, if possible.
I measured it again and guess what - it is now 2.93 volts. Sorry about that - I'm embarrassed.

I have Socket Kits put together now. Happy to send you one! That goes for anyone else beta testing too. Let me know if you'd like a Socket Kit and/or another Breakout kit along with it.

I have two more T4's arriving from PJRC tomorrow. They both will ultimately end up on break-out carriers (as will all future boards). Given my bad luck with the flex cable and standard size headers, I would love to rebuild the current unit with low-profile headers and get going on my system redesigns for T4 with all pins up and running..

Would it be possible to get another complete breakout kit + a socket kit + another flex cable(for the current board)? I'll be very happy to pay for it!

BTW - Mouser seems to a good supply of the Samtec low-profile headers... I didn't check them all but the ones I looked at were all in-stock.

Thanks for all your efforts,
Derek
 
@mjs513 - Will keep fingers crossed. Also will again first try washing with hot water and then dry first to hopefully remove as much flux residue as possible...

I always use rubbing alcohol with a good scrubbing with a toothbrush (preferably not your current one) and then mop up carefully with a paper towel to absorb the residue.
 
@mjs513 and @DerekR and ... @tallDog - I think I screwed up same way ... I waited for it to be dry... after cleaning... And teensy does not respond... I think I may have been just enough unaligned that it probably shorted things out... I may try to see if I can resurrect most of this T4, by trying to unsolder the ribbon... :(


@talldog - I am willing to try again if you are ...

Note I only cleaned with water and old toothbrush. As I am using the water soluble flux and solder that Paul suggested earlier.

EDIT: I was able to remove the flex cable (took some/most of the SDCard and probably USB Host pads with it, but at least should be able to at least use the main pins and other pads with the SMT connection...

EDIT2: Connected it up and no SD no USB, but do have pins 0-33 so not is all lost.
 
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I measured my battery and my cheapo meter showed 3.25V.

My flux ends up tacky { not sure if from solder core or my paste tub } - so if not all gone when I hit with a paper towel I get paper fibers on the board. So even the 90% alcohol needs some flush and scrub to be gone. I had a Flux Pen and it had bad control for my use - I got Flooding and then it went dry before too many uses. Maybe I didn't get the quality one - but flooding is bad with heat transfer and 'fluxivity' to close parts.
 
okay got the sd card socket mounted, the flex connector, 3 caps and the chip, the usb socket, and the switch. took some pictures will share them in a bit.
 
okay here are two pictures
 

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Nice pics - that even captured the USB chip label '|S11' - and lots of flux goop. Printed them for my assembly reference in a few hours ...

Glanced last night and the SD pins under shroud are reachable - at least with tinning and solder paste in place - would be nice if that could be removed/replaced - but I suppose that is the card Stop - not sure if it may give noise shielding as well?
 
Nice pics - that even captured the USB chip label '|S11' - and lots of flux goop. Printed them for my assembly reference in a few hours ...

Glanced last night and the SD pins under shroud are reachable - at least with tinning and solder paste in place - would be nice if that could be removed/replaced - but I suppose that is the card Stop - not sure if it may give noise shielding as well?

the shroud does slide off actually and it would provide shielding a bit if its soldered down.

and thanks :) took them with my t2i and then cropped for the forum.
and yeah I gotta clean it yet.. gotta go get a bottle of the purist rubbing alcohol I can get and a tooth brush just for this :)
 
Indeed I got the SD shroud off - and seemingly back on after making it look like it was soldered :)

Then I got the Ribbon connector to 'look' soldered.

I gave up trying to hack up short AdaF sized headers - and just decided I'd commit the T4 on pins. (@loglow) I did add a second set of spacers on the T4 corners to raise the T4 off the PCB - it was rocking on the '10 pin' 2x5 and not going tight with single spacer.

Ran out of time to fully complete it, soldered other SMD parts and a couple of pins to T4 and breakout that I thought would allow testing - but PCB not cleaned of FLUX:: 5V, GND, PGM, POWER, VUSB ( since I cut the trace ).

I CAN STILL UPLOAD CODE - slide switch works - POWER OFF/ON works - SD and USB not working with MSC test sketch - hopefully just flux on USB power and other bits. But next step will be to re-run the posted PinTest on the SD signals coming to breakout side pins that will show that much of flex cable made it through the connector.

When I see more signs of life there I'll fully solder the other 35 bottom pins and the other 22 top side pins and then 90% alcohol brush clean and dry - then retest. Otherwise I'll undo the T4 ( the solder I added to those few pins is only half tacked ).

bot_013147.jpgend_013747.jpgtop_013226.jpg

The end photo was to show the spacers - but I cropped too much - I only added two pieces of spacer on three corners - the corner shown has a length of 4 spacers since it is interrupted with the corner piece picking up the VUSB.
 
Well guys. I tried to solder up another T4, no ribbon, and managed to kill another T4. Not sure if I am will to try a third. Think if I was going to do this again I would use full size headers. But probably will.

@defragster - glad sliding the cover off helped :)
 
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@mjs513 - Yikes Wonder what hit it this time? The bottom SMT connector?

I know you do all of the normal things, so I know this is all probably not helpful, but just in case... like check for solder bridges and probably clean the bottom where/if you soldered an SMT connector, and check for any stray solder, as there are lots of little holes near bigger holes that can easily short... Or if you cut the VIN/VUSB connection, that you provide power to the chip.... I did not cut my VIN/VUSB as was not planning to external power it.... YET...
 
@KurtE

Yeah - probably shorted something on the bottom when I did the smt header. I didn't cut the trace either. May have had a solder bridge on one of the bottom resistors. Tried to clean it but still no luck.

Actually that may be a good warning for the instructions.

And since you know I am a glutton for punishment I just soldered up a third one but this time I didn't tin the sd or usb pads (checked didn't have any bridges there) and left off the 5 pin header on the back. That was the other thing they had in common. All that meams can't test on/off and vbat. May get brave later :)

Anyway to make a long story short third time was the charm. Plug the board in after testing it outside the breakout and it started blinking very happily after I plugged it in. Will probably start testing later today. Have to make a home depot run for the wife - dirt and tulips :)

@loglow. The one thing I noticed is that I had to cut the smt pins just about in half before I could get T4 flush with the out side pins. You may want to see if you can get ones shorter or warn folks in the instructions.
 
@mjs513 - Yep I was/am using normal size headers and even then I am not sure it gets down completely flush...

Also with those SMD connectors, on a different board, I soldered one on and it was real easy to solder bridge over to those caps... Lost one of those caps... T4 sitting on shelf, not sure if it will work or not.

So when I did the next one, I actually used cutter and shortened the smt legs, some, such that the legs did not fully extend out to the end of the pads, which made it easier to solder.

This time I did not do that. But I tried to be real careful in alignment. I used some extra long breakout pins, that I put into breadboard. Did not solder them in. Then placed T4 upside down on them, then used some female headers going sideways to the pins of the SMT connector over to the regular pins on T4, to get it close to being in place. I then used lots of flux, put a little solder on iron. With one hand pushing down on headers holding down SMT connector, until I think everything was aligned, I then touched down the iron on a pin, to have solder tack it down. Did to other one on far end, and then soldered the rest down...

And again before applying power to Teensy, I washed it in hot water, with toothbrush, placed in oven... Until dry. Note using Water soluble flux (2331)...
 
@KurtE

I have been using full size headers for the edges of the T4 and a half height 2x5 on the smt connector on my breakout boards. So even when the smt connector is a little lower that the edge connectors it sits very well in the headers and don't have to trim the smt ones at all. Think the half height ones are not working for me. The instructions are going to have be pretty detailed for regular users I think
 
Ok finished putting male headers on the breakout and ran @KurtE's any pin. All pins ring out no problem except for the card since I don't have a cable to test with yet. Once I get that I will try more. Now going to try the missing on off pins.

EDIT:
On/Off button: Success it works :)
VBAT: TBD.

here are a couple of pics on how I would use it.
20190913_122656.jpg
20190913_122620.jpg
 
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Did a { reflow/futz/desolder/reflow/DVM } test cycle on SDIO/USB connector pins the past 30+ mins. USB WORKS to read SD card with USB Dongle!

Same SD card fails on SD Socket - going to hope that is FLUX to be washed. Added T4 Pin 13 through to the PCB and used posted kePinTest code and all pins #34-#39 blink the LED on command - and no apparent shorts.

Soldered the rest and commited the T4 to the PCB … then cleaned it and … waited … 91% alcohol evaporates quickly when heated with hair dryer - hopefully I'll wait long enough … not sure I did?

>> Going to let it sit some more … When it powered it ran and uploaded - now just failing power on, nothing hot and no sign of magic smoke I have heard about.

I see 5V on VIN - but no 3.3V. Pulled RTC vBat. Tried another couple times and what before was every couple times flipping the PCB switch is not yet working. Power on with button doesn't trigger RED bootloader LED.

It came up running - but turning off and on with PCB switch or my inline USB power switch it sometimes failed to power up? Thought it was the PCB Switch - but same with external?

Before noticing this I confirmed - when RTC battery installed that RTC clock is maintained. Power Off/On worked.

USB SD Dongle worked, Same SD on PCB SDIO still fails.

Will let it rest and get back to my day and update later.

NOTE:
Using the metal framed battery holder - suggest covering the closed end toward pins #20-23 with Kapton tape. Depending on where the solder holds those pins solder could contact. I wicked off some of the solder mounds and after put tape over the '+' cover too then Xacto trimmed.
 
Not sure what is up with the assembly? I see 5V on expected places : VIN, Switch, VHST, VUSB, and high side of two bottom caps? I see 2.5 (?) volts on POWER. Zero on PGM and Top CAP. Near half a volt on the RTC '+' case with no battery.

I don't see 5V anywhere on PINS it should not be.

Had Computer sound off - so didn't hear it start up. Testing with one probe on GND and the other - looked up and it was printing on TyComm - then went away? Current sketch is not a BLINK so it didn't tell me when it was alive.

NOTE: >> When Powered the POWER pin reads close to 3V when ON. When given the 5 sec GND of POWER to OFF the POWER pin returns to 2.3V … under 2.5V waiting for half second press to power on. This I observed during Beta and again just now on a second T4.

I was seeing about 2.6 V and it goes ZERO on pressing Button. Holding button 5+ sec it went to 2.3 V, suggesting it went to POWER OFF mode.

Repeated presses of POWER leave the POWER voltage at 2.3 - I can't get it back up over 2.5 - even removing power with no batter . When it was over 2.5 that would suggest power too weak to startup the MCU.

My probes could be smaller and I could use a 3rd or 4th hand for safe reading my hiPower SparkFun DMM - that and I don't know what else to probe and what to expect?

@loglow - I can send you this unit if you would like to see it - or
@Paul if you are reading to see where the T4 is stuck I could send for your review?


As posted I did my best to progress in steps and test as I went. WIth the pinned T4 in place I can't expect to remove the FlexCable and put it back in place - even raised up two spacers high.

I could cut out the spacers and cut the pins T4<>PCB and see if the T4 runs without the PCB connections?

As noted it ran a few times and tests before going away? Then switching off and on became intermittent. Perhaps a pocket of alcohol was shorting something and broke it without obvious heat or smoke?
 
@defragster - just out of curiosity did you check the flexcable for shorts or the voltages that are coming out to the sd card to see if there is any problems on the cable.
 
@defragster - just out of curiosity did you check the flexcable for shorts or the voltages that are coming out to the sd card to see if there is any problems on the cable.

Yes, to the best of my patience and ability - some notes in p#145. Did pin tests to breakout pins on PCB from the connector pin legs with DVM and then the PinTest sketch. Tried adjacent pins for shorts. And GND and 3v3 to opposite end of T4.

{ Note meant to post before:: Placing that connector is easy to get it stuck with pins raised above pads (rocked toward rear cable entry point) - meaning no physical contact and requires more effort to string solder to fill the gap - when too much solder bridges - that is easy to mess up and hard to correct in that tight space. Might have had better luck soldering Flex direct to PCB }

Not sure how to evoke USB D+/D- , but when powered the Dongle SD worked USB to run the MSC Log Write test multiple times started when SD did not work. That SD card was also tested then to still work on PC.

I just did a more exhaustive Alcohol splash rinse - brush - rinse top and bottom. Patted with paper towel - swung it - then hair dryer baked a minute in hand until it was too hot to hold. Going to let it sit and go run an errand - will test again on return in maybe 2 hours.
 
I have never known excess flux on boards to create device function problems. For short-term prototyping projects I often don't bother to clean it up at all. But it sure makes the boards look spiffy. :cool:

I'm wiring up a board that will serve as my basic prototyping platform for the T4 on the carrier. It will have a PJRC TFT display, Audio card, pots and rotary encoders, an I2C port expander, etc. It'll take a day or so to finish the wiring (I use 30 AWG wire-wrap wire for the point-to point stuff).

So far the breakout continues to function except for the three broken GPIO pins on the flexcable.
 
Back home - IT SEEMS TO BE WORKING WELL

… more uploads to T4 and notes shortly …

All was well - did simple sketches and USB SD Dongle test no problem … moved SD card to SDIO socket and it failed to find the card again - then went dark … unplugged a minute and pressed buttons to drain caps and repowered to bootloader and went back to USB Dongle SD and all is well.

It seems something not right in the SDIO wire soldering. Will test a hard drive or two on USB, and use the Edge pins for SDIO's #34-39 as I/O to read write values with three of them wired to the other three in turn and see if that flies. Then will check the GND and 3.3V wires for shorts or odd voltage.

Given that the SDIO is mounted to PCB - would it make sense to not carry the GND and 3.3V lines through the Flex cable, but pull from the T4 pins? That would prevent an alternate design with daughter board using the Flex cable for all signals though - of course USB doesn't work without 5V and GND from PCB

Just put the RTC vBat back in - USB SD ran fine with clock set by TLoader. Did POWER Off and restarted … and it completed USB SD test run. back in a bit … leaving it running a RTC aware TempMon test program … cut power and it restarted with power knowing the time.
 
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