suggestion: teensy 3.x usb device with serial nor flash

pix-os

pix-os

Well-known member
hi all, i wondered if it is going to happen to get the teensy 3.x set up as a usb 'stick' using a serial NOR flash. (much like the teensy 2++ had with a microsd)
i could use a microSD , but it's way too large for a space-limited system like a smartwach.
 
Smartwatch may be an example of a product that needs to use die, not packaged products. MCU, mass storage (1 or 2 die depending on approach), etc. High NRE. Smaller size/height and lower BOM cost.
 
A smartwatch is a project I'm working on, i need to be able to put apps on a spi flash IC for the watch to execute (interpreter, or native code)

I don't prefer using a serial based approach though, but more like where one can use a window manager to copy apps to the spi flash (with help of the Teensy 3 mcu)
 
Eventually I'm going to implement MTP. Now that the prop shield is almost out, it'll be much more urgent. But that still doesn't mean there's going to be a solid timeframe.
 
MichaelMeissner said:
Over in the announcement forum in the prop shield thread, Frank B posted a utility to download to/from the Teensy Propshield's flash memory. It may be all you need to do is make some modifications for your CS pin, etc. https://forum.pjrc.com/threads/33328-Prop-Shield-Beta-Test/page12.

Of course, it would be more useful if it could work automatically, and the Teensy could emulate a USB removable drive or a MTP device.
Click to expand...

It could work automatically if there was a mode "Serial + Raw Hid"
But for now, the only issue is, that you must select "Raw Hid" from the menu.

It can write/read the internal EEPROM (not MAC, currently,...nobody tested the mac executable so far, so it is an old version and it will stay old until someone says "it works".) , too and SD soon.
 
Last edited:
pix-os said:
@frank b

perhaps adapt the code to work like this instructable? http://www.instructables.com/id/How-to-Design-with-Discrete-SPI-Flash-Memory/?ALLSTEPS
it allows one to program a spi flash over the serial :)
Click to expand...

Hmm. Why serial ?
I considered it before writing this utility and decided to use hid because its more easy to use( dont need to know the comport) and other reasons.
When i have time i try to add a serial+hid usb mode for the teensy. But it needs patching the core, unless Paul decides to add such a mode to Teensyduino.

Have you tried teensytransfer? Id like some feedback...
 
Last edited:
i can't try teensytransfer as i don't have a spi nor flash at hand, but i will soon though so i can test and give feedback :)

one thing i noticed though is that there's no option to order files by name, size and so on.

also, i would love to have a flash usage monitor which checks if the file can be uploaded or if the flash is becoming too full.
 
With linux (and MAC??), maybe the "sort" command is useful. Teensytransfer outputs to stdout, so it should work.

But i didnt try it, yet
 
This works on windows for sorting by name: teensytransfer.exe -l | sort /+8

With the sizes left justified I cannot sort by file size, this would be a problem elsewhere I assume as well unless they are left side blank padded (to 7 characters if limited to <10MB).
 
defragster said:
This works on windows for sorting by name: teensytransfer.exe -l | sort /+8

With the sizes left justified I cannot sort by file size, this would be a problem elsewhere I assume as well unless they are left side blank padded (to 7 characters if limited to <10MB).
Click to expand...

Thanks :) I'll update it to right-justified output today.
 
Last edited:
You must log in or register to reply here.
Back
Top