T4.1 ethernet and usb host pin alignments/dimensions

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PhilB

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I think I've got this right but just wanted to get a quick review. Here is a drawing I've done. Any correction needed? I'm assuming all the pins are spaced 0.1"/2.54mm. I plan on making a board that would have the MagJack and USB host connectors on it so would solder (or socket) the T4.1 with all it's pins in place.
pin alignment.png
 
Yes, the ethernet connector 2mm spacing and is centered between pins 20 and 21. It also has smaller holes, appropriate for the smaller 2mm pins.

Also, I believe that the vertical (in your drawing) distance between the centers of the USB Host and outside pins is 3mm, not 2.54mm. The pins in that line are offset by 1.27mm as you show.
 
Thanks guys. Very helpful! I looked at the 4.1 beta thread and see discussion about the 2x3 2mm spacing header but nothing about the positioning of that header on the T4.1 (though it's a long thread so I might have missed it). It looks like it is X aligned (X as in my drawing) between pins 20 and 21. Still not sure about the Y alignment. Looking closely at the photo and measuring it, it appears the center line of the top two holes of the 2x3 header is 2.4mm from the line defined by the center points of pins 20 and 21. See updated drawing. I replaced the header with a 2x3 2 mm spaced one. Hoping someone can verify the 2.4 mm spacing as the photo I measured it from is pretty low resolution. I will fix the hole size once I get the spacing correct (though larger holes might save slight misalignment...).
pin alignment.jpg
 
That matches what I've measured with my (cheap) calipers. Here's a high(ish) resolution photo of my beta board front:

IMG_7543.jpg
 
Thanks! Based on your photo, I think it's 2.5 mm. The ruler is extra helpful. That's into splitting hairs territory but hey, when ya got 'em, split 'em.
 
I can confirm the center coordinates for these connectors:

USB Host: 500, 170

Ethernet: 600, 475

These are in mils (1/1000 inch), relative to the bottom left corner of the PCB.
 
Many thanks Paul. Would it be possible to give the dimensions relative to the centre of pin D32 (bottom left hand corner of the Teensy 4.1) as the edge of the board isn't an absolute co-ordinate for those of us making a pcb footprint.
Also can I assume that the row of pins running from 38 to 27 follow the same convention as the Teensy 4.0. i.e. Vbat, 3.3V GND, Program, On/Off
 
@PhilB - just FYI, there's a related thread - https://forum.pjrc.com/threads/60846-T4-1-Ethernet-board

plus

0820-1X1T-00-F_SPL.jpg
https://www.mouser.com/ProductDetai...=sGAEpiMZZMvQhAhQbXdbBhrEwE4Ds1jHaYqXdbGAlwg=

and

https://forum.pjrc.com/threads/60846-T4-1-Ethernet-board?p=238950&viewfull=1#post238950

Are you planning to have the shield match the 18mm width of the Teensy and locate the RJ45 and USB A on the same side/in the same plane as the on-board micro USB?
Is that even remotely possible (willing to sacrifice pins)?

Asking for the friend of a friend
 
board

@PhilB - just FYI, there's a related thread - https://forum.pjrc.com/threads/60846-T4-1-Ethernet-board

plus

View attachment 20209
https://www.mouser.com/ProductDetai...=sGAEpiMZZMvQhAhQbXdbBhrEwE4Ds1jHaYqXdbGAlwg=

and

https://forum.pjrc.com/threads/60846-T4-1-Ethernet-board?p=238950&viewfull=1#post238950

Are you planning to have the shield match the 18mm width of the Teensy and locate the RJ45 and USB A on the same side/in the same plane as the on-board micro USB?
Is that even remotely possible (willing to sacrifice pins)?

Asking for the friend of a friend



If you get to the board stage, I'd be getting a couple of them,
 
Hmmm, interesting idea. I'm currently working on a CNC breakout board for grblHAL (32bit ARM version of the now-long-in-the-tooth grbl that runs on plain old arduinos). It does have an ethernet jack on it. Current status is I have first PCBs back, soldering on components (taking a break to catch up on email and such).

But the various comments made me go look at the idea of daughterboard for the 4.1 that supports both USB and ethernet jacks. Mechanical support is a concern - stress from two wires plugged in could easily overwhelm the 11 pins, even if soldered. The width issue is another one but moving the jacks forward or back might allow a slim fit.

Another thing I'm worried about is interference between the T4.1 and magjack. The literature is full of warnings about not running traces under the magjack. A bit of standoff might mitigate any problems. Worth trying.

I took a shot at a layout but am not happy with it. Needs some rework. Will probably have some time in the next couple of days - rain is predicted and the "honey-do" list is mostly outside...
 
@PhilB - just FYI, there's a related thread - https://forum.pjrc.com/threads/60846-T4-1-Ethernet-board

plus

View attachment 20209
https://www.mouser.com/ProductDetai...=sGAEpiMZZMvQhAhQbXdbBhrEwE4Ds1jHaYqXdbGAlwg=

and

https://forum.pjrc.com/threads/60846-T4-1-Ethernet-board?p=238950&viewfull=1#post238950

Are you planning to have the shield match the 18mm width of the Teensy and locate the RJ45 and USB A on the same side/in the same plane as the on-board micro USB?
Is that even remotely possible (willing to sacrifice pins)?

Asking for the friend of a friend

By the way, the datasheet on that makes me think it's a passive RJ45, no magnetics. I might go spelunking mouser/digikey...
 
I found one that might work. The Bel 530-0821-1X1T-36-F

Did a quick layout but there are issues using it for a daughter card atop the T4.1:
- it needs to be a bit wider than the T4.1 (850 vs 700 mils). It might be possible to squeeze another 50 mils or so...
- if the jack is mounted forward of the USB and 6 pin ethernet connectors (to the left in the 4.1 card view), the card needs to be high enough above the T4.1 to provide clearance to a plug in the microUSB connector. - probably 300 mils or more. Not sure how sturdy that would be.
- if the jack is mounted behind (to the right of) the connectors it forces the card to be wider because you don't want to route signals under the magjack. (might not be true with this connector because the USB receptacle is at the bottom of the stack - anyone have thoughts on that?)

Anyway, this was a good exercise for me as I am thinking about adding it as a version of my T4.1 grblHAL breakout board to allow a USB based pendant for CNC control. I have an eagle lib device is anyone is interested.
magjack.png
 
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Eagle Lib

I found one that might work. The Bel 530-0821-1X1T-36-F

Did a quick layout but there are issues using it for a daughter card atop the T4.1:
- it needs to be a bit wider than the T4.1 (850 vs 700 mils). It might be possible to squeeze another 50 mils or so...
- if the jack is mounted forward of the USB and 6 pin ethernet connectors (to the left in the 4.1 card view), the card needs to be high enough above the T4.1 to provide clearance to a plug in the microUSB connector. - probably 300 mils or more. Not sure how sturdy that would be.
- if the jack is mounted behind (to the right of) the connectors it forces the card to be wider because you don't want to route signals under the magjack. (might not be true with this connector because the USB receptacle is at the bottom of the stack - anyone have thoughts on that?)

Anyway, this was a good exercise for me as I am thinking about adding it as a version of my T4.1 grblHAL breakout board to allow a USB based pendant for CNC control. I have an eagle lib device is anyone is interested.
View attachment 20385

I know this is a very old thread but YES ! i would be highly interested in this board. can you please post the grbl or a link to.

Regards,
Marathonman
 
You can order a board from OSHPark. There are two to choose from
The board shown above[1]. $7.90 for 3
A wide version with mounting slots. $8.35 for 3
The wide version is basically the same as the other one just wider and uses the BOM from the first version.

I have built and tested the first one. I believe someone from this forum ordered and built the second one. There is a thread on that somewhere.

[1] The board in the above post has an error - the USBHost pins are rotated so it could not sit on top of the Teensy 4.1, the shared OSH designs are correct.
 
On a slightly different topic, I have a new version of the Teensy 4.1 grblHAL board coming that routes the HostUSB pins to a USB A socket. The purpose of that is to allow USB MPG/Pendant/game controllers/... to be used with a CNC machine. Currently in beta test and should be shipping in June.
 
I would like to get the RJ45 and USB together in one package that will connect to Teensy 4.1. i am swamp right now on the ranch or i would design myself.
thanks for all the work.

Regards,
Maraathonman
 
Ordered the OSH Park design and B.O.M, Thanks very much. these fake purposed shortages and rate hikes are killing everyone. it may be a redistribution of wealth but i have my Teensy 4.1 and i am happy. i will be posting my electronically switched active inductor controller design powered by a Teensy 4.1 soon.

Edit; Magjack is NO Where to be found until 7/30/21 at Mouser.
 
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Zero in stock at Digikey, too. Looked on findchips - sold out everywhere. sheesh.

Edit: You may be in luck! The Abracon ARJE-0032 is said to be a direct (ie, pin compatible) replacement. I looked at the datasheet and it appears to be true. In stock and slightly less expensive. Before buying you should verify the compatibility.

Datasheet
DigiKey page
Mouser Page
 
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Outstanding find, after reviewing the spec sheet seems a likely replacement. all of the pins are in the right place. very good find PhilB and thank you.
Regards,
Marathonmen
 
I forgot how slow Osh is, a while back i ordered from OSh and from China PCB mfg and the China one came in first.
on a different note, i ordered my Teensy 4.1 shift register timing board from JLC and i was surprised that their quality way better then that of PCBWay. all the drill hole were consistently off with PCBWay on many orders.

my order from Mouser comes in today and i will test shortly the Abracon ARJE-0032 replacement and post results on here as a viable replacement that "IS IN STOCK".

Regards,
Marathonman
 
Yeah, OSHPark runs about 8-10 days with the default options. You do anything different (like black mask), it will take about 2 weeks.

I have used PCBWay and JLCPCB. I don't recall significant alignment issues with PCBWay but I am mostly happy with JLCPBC. For bare boards, I often get them in less than a week with DHL. JLCPCB sometimes has mask alignment issues and they do this weird 20ish degree rotation of octagonal pads.
 
I am wondering if you have a placement for the parts like where to solder what caps and such at what point. the board does not say. there is no capacity designations.

EDIT; Never mind, i found it thanks.
Regards,
Marathonman
 
I soldered the Board when i realized the offset of the board is unreal. why did you not shift the pins over to account for the lining of the board to the Teensy, there is plenty of room to do this???. the board lines up on one side yet sticks out fare on the other side. also the pins you recommended do not jive with the Teensy board.
it seems a little more thought should of been put into this project. the board looks really bad sticking so far off to one side and had i of known this i would not have purchased it. i think i will redesign the board to make it a little more pleasing to the Teensy 4.1.
also the soldered pins are resting on top of the USB which makes it hard to connect to the computer to reprogram.

testing will commence when i figure out what the heck is wrong with the power issues of the Teensy 4.1.

i do not recommend for prime time just yet, sorry PhilB.
Regards,
Marathonman
 
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