SD card doesn't work on pysense

[freddy]

For some reason i can't get the SD card working in my pysense, i use a 16 GB microSDHC card.
Even the example code doesn't run:

from machine import SD
import os

sd = SD()
os.mount(sd, '/sd')

os.listdir('/sd')

f = open('/sd/test.txt', 'w')
f.write('Testing SD card write operations')
f.close()

It gives the following error;

Traceback (most recent call last):
File "<stdin>", line 6, in <module>
OSError: the requested operation is not possible

does anybody know a solution? Thanks in advance!

[jmarcelino]

@freddy
Can you try to format the SD card on the Pysense?

import os
from machine import SD
sd=SD()
os.mount(sd,'/sd')
os.mkfs(‘/sd')

[freddy]

@jmarcelino tried it, i get exactly the same error

[jmarcelino]

@freddy
Can you try another card please?

[freddy]

@jmarcelino made a little bit of progress, was abble to read out the content of the card, however suddenly out of nowhere a new issue popped up, i get the following error:

Traceback (most recent call last):
File "<stdin>", line 13, in <module>
NameError: name 'SD' is not defined

Do you maybe know a fix to that?

[jmarcelino]

@freddy
That seems to mean the SD module hasn't been imported, did you do from machine import SD first?

[Henning]

I have the same or a similar issue. Upon sd = machine.SD() I get "OSError: the requested operation failed
MicroPython v1.8.6-849-83e2f7f on 2018-03-19; FiPy with ESP32"

import os
import machine

### SD Card
sd = machine.SD()
os.mount(sd, '/sd')
# check the content
os.listdir('/sd')
# try some standard file operations
f = open('/sd/test.txt', 'w')
f.write('Testing SD card write operations')
f.close()

[jmarcelino]

@henning
Please follow the format procedure I posted below:

https://forum.pycom.io/post/19664

If it still fails try another card.

Thanks

[Henning]

Thanks for your reply. The problem is that I get the error already on the sd=SD() line. Which fileystem does pycom expect or which is recommended? Currently the card is fat32 formatted.
I'll try to get a different card to test too.
@jmarcelino said in SD card doesn't work on pysense:

@henning
Please follow the format procedure I posted below:

https://forum.pycom.io/post/19664

If it still fails try another card.

Thanks

[Henning]

I tried a brand new 32GB SD card and get the same error.

Code

from machine import SD

sd = SD()

Output
OSError: the requested operation failed
MicroPython v1.8.6-849-83e2f7f on 2018-03-19; FiPy with ESP32

Version:
>>> os.uname()
(sysname='FiPy', nodename='FiPy', release='1.17.3.b1', version='v1.8.6-849-83e2f7f on 2018-03-19', machine='FiPy with ESP32', lorawan='1.0.2', sigfox='1.0.1')

I'm using the SD slot of the pysense board.

Any ideas on what might cause it to crash at this early stage or how to debug the issue?

[CharlesDarwin]

@henning I am getting the same error using a FiPy on a PyTrack board. This is really frustrating.

[timh]

@charlesdarwin I have FiPy with Expansion board 2.0 and SD mounting is fine, as long as there is a card present and it's got Fat32/Fat16 FS I only use Sandisk.

[jmpratt]

@freddy I was having a problem reading the SD card on a Pytrack and a WiPy 3.0. I formatted the card in a USB adapter on a Windows 10 machine to FAT32. Initially, the WiPy could read it just fine so I wrote sd_boot.py to the SD card. Boot.py would run sd_boot.py if the SD card is present. After a couple minutes, I could no longer read the SD card but it was still mounted. If I rebooted the WiPy, it would still find and run sd_boot.py but I could no longer FTP to /sd/ nor see it in the REPL window (os.chdir('/sd') would give an error).

I reformatted the card while inserted into the PyTrack via the os.mkfs('/sd') command (as shown below) and now it works fine. Seems like it didn't like the way Windows 10 formatted the card.

[combaindeft]

@jmarcelino

Well, I have the same issue as the original poster... tried all ... and still it fails.

The odd thing is ... all of the SDCards work with all of your PyTrack's .... really off that that they don't work with the PySense ...

[timh]

Hi

Having the same experience with Expansion Board 3.0.

After power up I can write some of the time if performed early (sometimes).

Leave it 20min powered up and no chance of writing.
Exception message - operation is not possible or OSError: [Errno 5] EIO

Can read most of the time.

Sometimes unable to call SD()

Only use Sanddisk and FAT32.

This most frustrating.

T

[combaindeft]

Update:

I figured it out why it failed on one of our PySense boards ... after closer examination it looks like the pins on the board ... poked holes in the LiPo Battery pack we used ... and this must have shortened something inside the PySense ... ergo, it looks like it's the SD-Card controller that got fried or so ...

In other words, not really a software issue this time around :-)

[timh]

@timh I have narrowed down why I can't write to SD card.

If i2c is being used then writes fail. (reads don't).

By not enabling I2C writes are successful.

I am using PINS P22 and P23 for I2C. This worked on Expansion Board 2.0
I cannot find anything in the docs regarding a potential clash with this choice of PINS.

Am now going to experiment with deinitialising the i2c devices before reading/writing SD.

;-(

[robert-hh]

@timh P23 is used for SD card clock. That is shown in the Pin-Out.

[timh]

@robert-hh

I have even tried disabling I2c before writing to SD, but this doesn't work.

Bit stumped.

[robert-hh]

@timh The reason might be, that even if you deinit I2C on that Pin, it is not re-init'ed for SD card use. Without looking into the code, I assume that this is done when instantiating the SD object with
sd = machine.SD()