Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 6 of 6

Thread: Using W25N01 NAND Flash and PSRAM

  1. #1
    Junior Member
    Join Date
    May 2020
    Posts
    11

    Using W25N01 NAND Flash and PSRAM

    I tried using a W25N01 NAND flash memory chip (W25N01GVZEIG from Digikey) and a PSRAM chip (from PJRC) on a Teensy 4.1.

    I could not get the NAND Flash to work on the narrower pads, but it worked fine on the wider pads. I used the LittleFS_QSPI_Simple_Datalogger.ino example to test it.
    It is almost impossible to solder the W25N01 to the narrower pads and so it may be that I had a soldering error in that case.

    So I tried putting a PSRAM chip on the narrow pads.
    But I can't get the 8MB PSRAM chip to work when installed on the narrow pads when the WS25N01 is present on the wider pads.

    Click image for larger version. 

Name:	T4pt1_PSRAM_and_WS25N01.png 
Views:	10 
Size:	760.2 KB 
ID:	25972

    I tried putting an image above.
    Can this be done or have I done something that is not supported?
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	T4pt1_PSRAM_and_WS25N01.jpg 
Views:	12 
Size:	52.8 KB 
ID:	25971  

  2. #2
    Senior Member+ mjs513's Avatar
    Join Date
    Jul 2014
    Location
    New York
    Posts
    7,555
    Definitely can be done. The W25N01 is supported is that slot using LittleFS. There are a examples in the LittleFS library that should help guide you.

    In addition the Readme of the LittleFS Teensy library: https://github.com/PaulStoffregen/LittleFS, provides additional guidance. Look for the QSPI simple data logger example.

  3. #3
    Junior Member
    Join Date
    May 2020
    Posts
    11
    Thanks mjs513.
    The W25N01 IS working (I am very happy about that!) with the LittleFS library using the LittleFS_QSPI_Simple_Datalogger.ino example you suggested, but I could not get the PSRAM to work with it.
    Paul's memory test, https://github.com/PaulStoffregen/te...am_memtest.ino , shows 0 memory.

    I'll try another chip. I use the PSRAM in many projects and hadn't had any trouble so I thought I might have tried something that was not supported.
    Thanks again!

  4. #4
    Senior Member+ mjs513's Avatar
    Join Date
    Jul 2014
    Location
    New York
    Posts
    7,555
    Quote Originally Posted by SR61 View Post
    Thanks mjs513.
    The W25N01 IS working (I am very happy about that!) with the LittleFS library using the LittleFS_QSPI_Simple_Datalogger.ino example you suggested, but I could not get the PSRAM to work with it.
    Paul's memory test, https://github.com/PaulStoffregen/te...am_memtest.ino , shows 0 memory.

    I'll try another chip. I use the PSRAM in many projects and hadn't had any trouble so I thought I might have tried something that was not supported.
    Thanks again!
    We used both together before without any issue so maybe try reflowing the soldering on that PSRAM. And sorry misunderstood.

  5. #5
    Junior Member
    Join Date
    May 2020
    Posts
    11
    So...

    I desoldered the PSRAM from the Teensy, and soldered the chip to another Teensy by itself and ran Paul's memory test and it worked.
    So I desoldered it and put it back... and it works. So it must have been a soldering error.
    I evidently made a poor connection or left a whisker of solder across pads and did not see it.

    Thanks for your help! I really appreciate the work everyone at PJRC has put into the hardware, software and support.

  6. #6
    Senior Member+ defragster's Avatar
    Join Date
    Feb 2015
    Posts
    15,093
    Good it worked with all the extra soldering! I've had good luck with PSRAM's ( and flash ) on the T_4.1 QSPI pins - two more ahead tomorrow for testing in some fashion.

    As noted by @mjs513 - reflowing solder ( with added flux ) then assuring their are good connects with no extra connects - then removing the flux and making it clean is good and this case is the 3rd or 4th where PSRAM worked when the solder was good.

    Congrats especially on removing/desoldering it twice! I've not gotten the hang of that yet - I usually end up cutting pins and removing the pieces and starting with a fresh chip ... but that was trying to repopulate some small flash breakouts with other chips.

    Just tried getting a WSON Flash ( to reuse ) off a board that went dead and never got it to move before giving up.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •