Teensy 4.0 Breakout Kit

With the onboard USB header - this may not be an issue worth change: The T_3.6 layout that allows a simple flexible PJRC USB_Host plug arrayed as :: 5V, DM, DP, GND, GND - where it comes between the CAN pins and T4 GND pin - this order isn't present. Leads to question: Does the TPS2055A chip control on those pins as well as routed.

Yikes! I totally forgot about this. Now I remember why those two GND pins were next to each other. I've put them back in order.

Extended question [ if relevant and of any value?] - the T_3.6 has a control line routed internally on a hidden pin AFAIK that disables the TPS until USB Host is enabled? Does the TPS2055A have that feature - With an added control pin the user could wire I/O of choice to that pin? Blackketter has a pin with trace cut pad for that on the USB sidecar.

The TPS2055A does have an EN pin, and I just had it connected to VIN. But...

What if there was a second switch that would connect VIN to either EN (for host powering device) or VHST (for device powering host)?
 
With the re-ordered USB host pins and the added second (USB host power) switch:
Teensy_4_0_Breakout_T.jpg Teensy_4_0_Breakout_B.jpg
 
@loglow, - Maybe it was just me, but with the first version, I found using my 10 left thumbs, that it was hard to solder the front connector as well as the SD Card slot. Which one should you try to solder in first? With the card adapters from round one, you could not easily see, let alone easily solder from the back. It was sort of the chicken and egg. I know several of us resorted to removing the top of the SD adapter, but in many cases we had difficulties, getting it properly back on. Mine did not work, but then again there was an issue of two pins shorting out on ribbon, so I totally removed the SD stuff.

For me, the ones like on FRDMs board or Paul's break out where the SDCard can be soldered in from the front, but most of them I have seen require more space on the board. So hopefully it might just be we needs some precise instructions on how to properly get these two parts properly soldered on. Although it might be interesting to see how much extra room as the back end could move closer to the connector for the ribbon, which would then clearly need to be soldered on first.

New battery holder? Did you go with one that the battery goes in from the top(or bottom) and not out the sides? i.e. if I configure this for a breadboard, probably removing the outer rails, can I get a battery in and out?

Thanks again
Kurt
 
I'd like to do another round of beta testing on these, so please let me know if you're interested!

Best,
Dan
I wasn't part of the first round of beta testers, but I would like to be added to the current round if you have room. Let me know what specific parts I would need to order (presumably from digi-key).
 
@loglow, - Maybe it was just me, but with the first version, I found using my 10 left thumbs, that it was hard to solder the front connector as well as the SD Card slot. Which one should you try to solder in first? With the card adapters from round one, you could not easily see, let alone easily solder from the back. It was sort of the chicken and egg. I know several of us resorted to removing the top of the SD adapter, but in many cases we had difficulties, getting it properly back on. Mine did not work, but then again there was an issue of two pins shorting out on ribbon, so I totally removed the SD stuff.

I think it will be easiest to solder the SD socket first, but it will also be easier now that the pads are longer too. I'm going to do some experimenting. This round will have step-by-step assembly instructions (with photos!) to test as well.

New battery holder? Did you go with one that the battery goes in from the top(or bottom) and not out the sides? i.e. if I configure this for a breadboard, probably removing the outer rails, can I get a battery in and out?

Yes, the new battery holder is a top-entry type. My hope is that it will work much better, and still be usable with breadboard headers in place too.
 
Im interested. I just obtained reflow soldering equipment, looks like good practice. Thanks in advance

I wasn't part of the first round of beta testers, but I would like to be added to the current round if you have room. Let me know what specific parts I would need to order (presumably from digi-key).

PM'd both of you. Thanks!

You won't have to order any parts. They'll be included :D
 
That's a really clear bit of documentation. Well done. Can I ask how you made it?
Yep it is a nice set of cards!

Just an FYI, for other forms of the data:
There is a table of all of the pins in the Beta thread: https://forum.pjrc.com/threads/54711-Teensy-4-0-First-Beta-Test?p=193716&viewfull=1#post193716

I have most of the same data in my Excel spreadsheet I made during the T4 beta, now up on github: https://github.com/KurtE/TeensyDocuments/blob/master/Teensy4 Pins.xlsx

During each of the recent betas, several of us have generated these tables from the information Paul put into the first beta builds, plus the reference manuals.

For example if you look at the file cores\teensy4\core_pins.h


You will find a whole lot of defines sort of in different tables...
Example sections like:
Code:
#define CORE_PIN0_BIT		3
#define CORE_PIN1_BIT		2
#define CORE_PIN2_BIT		4
#define CORE_PIN3_BIT		5
#define CORE_PIN4_BIT		6
#define CORE_PIN5_BIT		8
...

And
Code:
#define CORE_PIN0_PORTREG	GPIO6_DR
#define CORE_PIN1_PORTREG	GPIO6_DR
#define CORE_PIN2_PORTREG	GPIO9_DR
#define CORE_PIN3_PORTREG	GPIO9_DR
#define CORE_PIN4_PORTREG	GPIO9_DR
#define CORE_PIN5_PORTREG	GPIO9_DR

So we know that the first few pins are: 6:3, 6:2, 9:4, 9:5, 9:6, 9:8
Which side not show up as 1.3 1.2 4.4... in my table as this was done before mapping to faster ports (also was done originally during beta 1 with 1052).

And a Bigger Hint is the set of defines for the PAD control:
Code:
#define CORE_PIN0_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_03
#define CORE_PIN1_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_02
#define CORE_PIN2_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_04
#define CORE_PIN3_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_05
#define CORE_PIN4_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_06
#define CORE_PIN5_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_EMC_08
#define CORE_PIN6_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_B0_10
#define CORE_PIN7_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_B1_01
#define CORE_PIN8_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_B1_00
#define CORE_PIN9_CONFIG	IOMUXC_SW_MUX_CTL_PAD_GPIO_B0_11
This is actually showing the real underlying pins: GPIO_AD_B0_03, GPIO_AD_B0_02, ...

Now from this you can find a lot/most of the data associated with the pins in the IMXRT1060RM document probably the smaller document as well. But if you look starting in chapter 7 for the string GPIO_AD_B0_03 You will run into several places this pin can be configured. And you can find it a few different ways.

You will run into Table 9-1 muxing options like on P297 you find that it can be FLEXPWM1_PWM1_X when configured to ALT4, and FlexCan... GPIO1 (ALT5)
But the best place to find this pin is in section 10.7.46:
(IOMUXC_SW_MUX_CTL_PAD_GPIO_AD_B0_03
Which shows all of the MUX modes for this pin:
Code:
MUX_MODE MUX Mode Select Field.
Select one of iomux modes to be used for pad: GPIO_AD_B0_03.
000 ALT0 — Select mux mode: ALT0 mux port: FLEXCAN2_RX of instance: flexcan2
001 ALT1 — Select mux mode: ALT1 mux port: XBAR1_INOUT17 of instance: xbar1
010 ALT2 — Select mux mode: ALT2 mux port: LPUART6_RX of instance: lpuart6
011 ALT3 — Select mux mode: ALT3 mux port: USB_OTG1_OC of instance: usb
100 ALT4 — Select mux mode: ALT4 mux port: FLEXPWM1_PWMX01 of instance: flexpwm1
101 ALT5 — Select mux mode: ALT5 mux port: GPIO1_IO03 of instance: gpio1
110 ALT6 — Select mux mode: ALT6 mux port: REF_CLK_24M of instance: anatop
111 ALT7 — Select mux mode: ALT7 mux port: LPSPI3_PCS0 of instance: lpspi3

Now all you have to do is to repeat for each of the IO pins...
 
So we know that the first few pins are: 6:3, 6:2, 9:4, 9:5, 9:6, 9:8
Which side not show up as 1.3 1.2 4.4... in my table as this was done before mapping to faster ports (also was done originally during beta 1 with 1052).

Thanks, this is great.

So, what's your opinion about the ALT5 column in the PIN MUX table then?

Should it be left as-is:

GPIO1_IO03
GPIO1_IO02
GPIO4_IO04

Or changed to read:

GPIO6_IO03
GPIO6_IO02
GPIO9_IO04
etc.
 
Thanks, this is great.

So, what's your opinion about the ALT5 column in the PIN MUX table then?

Should it be left as-is:

GPIO1_IO03
GPIO1_IO02
GPIO4_IO04

Or changed to read:

GPIO6_IO03
GPIO6_IO02
GPIO9_IO04
etc.
Good question: I see arguments going both ways.
That is most of the documents talk about GPIO1-5, the main part the you actually find more on GPIO1->GPIO6 is in the definition of the register: IOMUXC_GPR_GPR26 - P371
And likewise for ....GPR27....29 for 2->7, 3->8, 4->9...


Not sure if anyone will ever muck with these registers... At one point I hacked up a test app, to see if it made a difference in interrupt response... don't remember if it did or not...
 
I changed the SD card socket. I have a feeling that some of you are going to be very happy about this.

The new one doesn't have any overhang, so it should be much easier to solder. It's slimmer too.

Teensy_4_0_Breakout_T.jpg sd_socket.png

The new part is Molex 1051620001

Also, I'm thinking about offering breakout kits with just the SMD parts pre-assembled.
 
That looks much better - with the cable first those pins can be soldered more easily and tested as good before putting the SD socket in place and then having easy access to those pins without risk to the cable socket pins - except the narrow mount pads on the back edge.

Hopefully the pin ordering is clear on that part - and those pins can then test out to match the cable signals.
 
I agree with @defragster. That SD socket is a lot better for soldering and testing. Having to remove the cover on the old one and put it back on was a challenge.

The cable is a lot better as well for soldering. Offering to have the SMD parts pre-soldered is a good idea for those of us that solder challenged on small parts :)
 
Edit - Don't have Annie (50 pound lap dog) sitting in my lap on my arms :D

@loglow - Thank you! Should make it a lot less error prone. Also having the option to have these parts pre-soldered would be nice. Not sure how much difference in price versus mostly assembled. I guess it leaves it for the User to solder two switches, USB connector and the Teensy, or more likely socket.

The only other possible error prone part may be in the alignment of the ribbon. Your new one looks more promising for this. That is one of the things I like about the FRDM design, in that you have multiple IO pins that connect between them and almost guarantee that you should have proper alignment.
However I think your new ribbon, looks very promising to help minimize the issue.
Not sure if it would help or not, but wonder if at the top and bottom of the ribbon, above Dat1 and below Dat2, if you exposed slight pads, that can be tacked onto the Teensy's SD Card connectors non-signal pads (the longer ones on top and bottom) - if that would help to allow one to tack one edge in or not... Probably not. But thought I would throw that out there...

Again thanks for all the work you are doing on this.

Kurt
 
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The only other possible error prone part may be in the alignment of the ribbon.

Yeah, it'll be interesting to see how this one goes.

You'll notice that I added two white line markings onto this version of the flex cable. They're designed to align with the existing white lines on the underside of the Teensy. Just another little added guide. The cable should be easy enough to tape in place before soldering, so I think alignment should go ok!

guides.png
 
@loglow --- Hey Dan,
For health reasons I've had to take a break from things Teensy over the past few weeks, and things got away from me. I am finally catching up and am delighted to see the progress you've made. Your "round one" board is still churning away 24/7 (with its couple of non-functional pins) with no other problems. I know I'm late to the game, but would be delighted if I could rejoin the current beta efforts at this late stage. No problem if you already have enough testers... happy to pay my way.
 
Yeah, it'll be interesting to see how this one goes.

You'll notice that I added two white line markings onto this version of the flex cable. They're designed to align with the existing white lines on the underside of the Teensy. Just another little added guide. The cable should be easy enough to tape in place before soldering, so I think alignment should go ok!

View attachment 18224

I did see that guiding white line and hoped it would look like the picture. Will help starting it squared up - of course after soldering it will just show how crooked it is :)

Assuming no duplicate silkscreen labels on the back side will make it easy to have it flipped the right way. Those T4 end gaps for GND and 3.3V should make that end of the cable much easier to avoid cross pin shorting and cleanup - and without electrical connectivity to cable pads less likely to cause damage if connected before proper test.
 
@Loglow - I know you are busy but I am Kinda curious if this breakout board is still on track?
Thanks:)
 
I just got the kit from Loglow/talldog. Thanks.

I suspect I may need to wait until the detailed instructions are done.

I was playing around with the PCB, and I dropped the coin cell battery holder. It took me some time to find it as it rolled to the furthermost corner under the desk at work and it blends in with the industrial carpet at work, and I will need some longer grabbers to get it.

But anyway, before dropping it, I noticed that was a rather tight fit between the battery holder and pins 21-22 and pins 3-4 that might be problematical if you solder the pins in first and then solder the battery holder on. I suspect the best way to attach is to put the female socket pins through the PCB, but don't solder them (or at least pins 3, 4, 21, and 22). Then attach the coin cell holder and do surface mount soldering. Finally solder in pins 3, 4, 21, and 22, taking care not to melt the battery holder.

My kit had a small coin cell battery in it. As you transition towards selling it on tindie.com, I wonder whether you will need to have different versions one one has the battery in it (that can be mailed easily with ground transportation to the lower 48 states), and one without a battery for outside the USA or to Alaska/Hawaii (and have the people source a battery locally). Now that battery is so small, I doubt it would be an issue, but regulations are regulations. Or possibly just not include the battery, and make evrybody source the CR1220 themselves.

I'm wondering whether the U1 and U2 SOIC mounts might be better to list the actual chip rather the U1/U2, to allow somebody to make sure they are soldering the right part.

There are 2x2 male and female headers, along with one 14-pin male/female header and one 12-pin male/female header. I assume the 2x2 headers are for VIN, Ground, Not used, and VUSB. If so, we probably need to pull out the pin left of the VIN pin. Is this correct?

At present, I have no plans to use CAN, but I might want to use the CAN pins. Should I just not solder in the MCP2558FD?

The socket kit doesn't have any parts for bringing out the micro-SD pins. I assume this is by design? How would you use the socket kit?

I would imagine there are a lot of people like me that aren't as comfortable doing surface mount soldering that having a board with the SMT parts soldered would be useful.
 
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@loglow
Dan,
I've assembled the new board - thanks very much for including me. It went very well, much smoother than the first Beta - took about 3.5 hours with quite a bit of time spent working out a sensible construction order. BUT - I hit a snag at the last step, ie as I was mating the T4 to the breakout. I found it impossible to insert the flex cable into its socket! I used the header kit, and the 2x2 female socket on the breakout prevents the flex cable from entering the socket properly, and although I struggled with it for quite a while I was not able to close the latch. I think the answer is to take out the 2x2 female socket and remove the unused corner (with a Dremel?)

But right now that's academic because disaster hit! I had assembled a brand new T4 to populate the breakout. It was working fine just on its own, dangling on a USB cable. I checked the breakout thoroughly for shorts - all ok - plugged in the T4 and,,, nothing. The Teensy is completely gonzo :( !!! There is no longer any 3.3v (yet 3.3v to ground is open on the breakout.). This is the fourth or fifth T4 that I have lost due to random failure of the 3.3v supply!!! (I leave my projects running 24/7 and the failures have all happened when I am nowhere near them, usually after a few weeks of running!!!), and all are running behind surge protectors. Makes me wonder if the T4 is truly ready for prime-time. I don't have any more spare T4's, so I'm now out of business for several days at least. Grrrr...

I'll send a photo of the flex-cable interference if that will help.
Derek
 
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