Teensy 4.1 Beta Test

This flash chip works for me. It is the same flash chip that can be soldered to the audio shields, and it gives 16 megabytes (or 128 megabits) of persistent flash memory:

The PSRAM chip is a lot harder to find. If you are ordering from PJRC.COM, they sell it for $1:

When I was looking around for the psram for my beta unit, I found it alibaba, and I ordered 10 chips on May 1st. In theory, it has been shipped, and there is a tracking number for it, but the tracking number isn't in the system yet.

If you go back on this thread, after I posted about trying to find the chips, somebody else mentioned another site that also sells it. Paul sent me a chip (this is before he added it to the store), and I soldered it onto my beta unit. I'll see if I can find the link. Since PJRC is selling the chip, USA buyers probably should buy it from them. Non-USA buyers may need to find other suppliers. Here is the other vendor:

Note, I believe the psram is not persistent memory, while the flash is persistent. I tend to view the psram as being the place to put large things like display buffers, while due to its persistent memory, the flash is perhaps better used like a sd-card with a file system emulation built on top. When I used the function to erase memory, the psram came back almost immediately, while the flash took about 25 seconds.
 
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Note, I believe the psram is not persistent memory, while the flash is persistent. I tend to view the psram as being the place to put large things like display buffers, while due to its persistent memory, the flash is perhaps better used like a sd-card with a file system emulation built on top. When I used the function to erase memory, the psram came back almost immediately, while the flash took about 25 seconds.

Indeed the Pseudo Static RAM chip will lose all stored data without power, and the only power it gets is from the 3.3V of the T_4.1.
In practice I have seen it survive across Uploads when testing SPIFFS. So a restart maintaining power keeps the power applied to the chip it seems. Startup and doing init access to the chip does force memory to clear.
 
16 MB is not bad at all.
Any tips about soldering those SOIC chips on the underside of the Teensy? Never tried to solder SOICs.

Look for a uTube vid or two for SMD solder and watch them. Prepare to solder a single pad get wet solder there and slide the chip in square and cool to tack it in place. Do the other pins to pads and then be sure to heat the pad and leg together on the first.
 
Found the problem and just committed a fix for this.

I got latest NativeEthernet from github.

Hmmm, not quite. Seems to fix 25 second delay before SYN packet, but if the server is not running for a while, then client eventually gets into a state where no SYN packets are being sent ??? sketch is just printing "connect failed". maybe fails after an ARP request shows up ?
Code:
06:16:29.461450 IP 192.168.1.113.8888 > 192.168.1.4.5001: Flags [S], seq 4416001, win 5840, options [mss 1460,wscale 0,eol], length 0
06:16:29.461485 IP 192.168.1.4.5001 > 192.168.1.113.8888: Flags [R.], seq 1477920147, ack 4224001, win 0, length 0
06:16:34.462502 IP 192.168.1.113.8888 > 192.168.1.4.5001: Flags [S], seq 5120001, win 5840, options [mss 1460,wscale 0,eol], length 0
06:16:34.462538 IP 192.168.1.4.5001 > 192.168.1.113.8888: Flags [R.], seq 1477920147, ack 4928001, win 0, length 0
06:16:39.468200 ARP, Request who-has 192.168.1.113 tell 192.168.1.4, length 28
06:16:39.468291 ARP, Reply 192.168.1.113 is-at 0a:1b:3c:4d:5e:6f, length 46
 
Quick Note: I did a little time wasting this morning and add another page to my Excel T4 pins document to have a card like version for T4 as well. So need to double check my cutting and pasting
is correct.

T4-Cardlike.jpg
 
16 MB is not bad at all.
Any tips about soldering those SOIC chips on the underside of the Teensy? Never tried to solder SOICs.

There are various videos on how to solder SMD. I tend to do it my own way.

Get the smallest solder wire you can find. The normal kester solder wire that I use is 0.031" thick. For the two memory chips, I was using 0.02" thick solder I picked up at my local electronics store. I see Amazon has 0.015" thick solder:

If you don't have one, get some form of magnification. I wear bi-focal glasses, and I have to make sure I position my head so that I can see clearly.

Make sure you have plenty of solder braid to remove excess solder.

Take your time.

Position the chip so it sits evenly within the pads. I used clear tape (aka, Scotch Tape [tm]) to tape the chip down, exposing 1/2 of the pins. Note, on the chip there is a dot. That dot should be lined up with the dot on the solder pads. The psram chip goes at the end of the Teensy 4.1 (smaller pads, aka SOC if I remember correctly) between pins 32-30 on one side and 33-35 on the other. The flash chip goes next to that with the larger pads (SOIC-8), between pins 30-28 on one side and pins 35-37 on the other.

Solder those pins, running solder from the legs to the pads. Take off the tape, and do the other pins.

Check with a volt meter in continuity test mode (i.e. have the VM set so it makes a buzzing if there is an electrical connection between two points) to make sure you don't have an unintentional solder bridge between the pads.

For the Teensy 4.1, all of the pins except for the pin nearest the dot are the same between the two pads. Use a volt meter, with one side touching the chip's leg, touch the other wire to the other chip's corresponding pad to make sure there is a connection between the Teensy 4.1 and the flash chip.

If you get multiple flash chips and you have an audio shield, you might practice first soldering a flash chip to the audio shield, and verify that it works using one of the Serial Flash tests.

As of Teensydunio 1.52 beta 4, the necessary drivers for SPIFFS, etc. weren't in the combined Teensydunio release. I found the location in an earlier post in this thread.
 
@MichaelMeissner
Good set of instructions. Pretty much what I do. I am using either the 0.02 or 0.031 Kester typically, forgot what my current spool is. Only thing that I am not currently using is the scotch tape to hold the chip down. Might be able to use high temp tape as well to protect the chip. Usually use tweezers but think the tape is the better way to go. But all the other steps are good advice.
 
Tested the T4.1 prototype with my stepper motor drivers and libraries yesterday, all works fine.

Also got my PJRC order in for a couple of production T4.1s and memory chips!

Don
 
I've seen on the Teensy 4.1 schematic, the TPD3S014 is fed through the fuse and the DMG2305UX with 5V from host. Now the TPD has reverse blocking and power limit on it's own. An unintentional overload, which may still be well within headroom for USB, may blow the fuse, plus a (still small) voltage drop on the DMG, I see no advantages of this connection over connecting the TPD directly to VIN. What was the intention behind the way how it is done now?
Edit: Also, a connected device may still feed noise into the the Teensy, because it is behind the inductor.
 
Sparkfun have them in stock now. No restriction on how many you can buy. When the Teensy 4.0 was release it was only 2 per customer.

Just ordered some.
 
Ok all. Since its safe to post pictures now going to post a pic of a RA8876 on a new breakout board I am planning on using for display tests. Has room for a ILI94 88 and a ILI9431 (both on are SPI1 but with different DC/RST/CS pins - NICE WORK KURT!). One has a tristate buffer. Also has room for a Adafruit 320x240 ST7789 and I threw on there room for a QWIIC adapter board for the heck of it: This shows one of the versatilities of the T4.1 since you don't have to play with underside pins :)
View attachment 20064

Board is looking good! Glad you can run multiple SPI busses!
 
Tested the T4.1 prototype with my stepper motor drivers and libraries yesterday, all works fine.

Also got my PJRC order in for a couple of production T4.1s and memory chips!

Don

Nice Don.

My order for T_4.1's to arrive Friday - I have PSRAM's and Winbond 16M Flash's on hand. Some PSRAM's ordered last year - take a long time to arrive ( more so now probably ) - Nice that Paul got some on hand - they run well when needed.

I got feedback from SFUN 'Features' edit comment (p#389) - now shows:
Code:
8 Mbyte Flash (64K reserved for recovery & EEPROM emulation)
2 chips Plus Program Memory
8 Serial ports
 
"Everyone on this list who does not receive a pre-production board will be offered a free Teensy 4.1" I was lucky enough to be on the list, do I need to email PJRC to get one? I am honored to have made the list but to tell the truth I am not sure what I did to make the cut.
 
I'm doing simple regression testing with a dozen or so of my lab setups, just to make sure interfaces and all look good. I just tested the BNO080 IMU with the Sparkfun lib over I2C, all looks good to me. Here's and example of the PRY output, Exp 17 in the lib.

-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4
-0.7,1.3,-124.4

Ok Don you inspired me to hook my BNO080 back up and merge it with the openGL 3D model of a Steampunk Blimp I got on line for testing. Works pretty good. Using defaults from the BNO080 library examples.

 
Ok Don you inspired me to hook my BNO080 back up and merge it with the openGL 3D model of a Steampunk Blimp I got on line for testing. Works pretty good. Using defaults from the BNO080 library examples.

That's cool @mjs513 - have you got that code re-shared anywhere?
 
"Everyone on this list who does not receive a pre-production board will be offered a free Teensy 4.1" I was lucky enough to be on the list, do I need to email PJRC to get one?

You'll get an email soon with instructions. So will everyone on the list who wasn't sent a early board. The message will go to the email you used to register on the forum, so if you used a different account, be sure to check that inbox.

Tomorrow we'll finish shipping the backlog of pending orders. Then we'll ship to everyone who responds to that email. I imagine most will ship Thursday.
 
When the Teensy 4.0 was release it was only 2 per customer.

We're not limiting how many Teensy 4.1 anyone can buy.

Though I can say nearly all the non-distributor orders have been for 1 to 5 boards, with most for just 1 or 2, so things worked out about the same.
 
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