File (ESP32 SDMode) longer string possible?

[stefan.erni]

Hi Ben

Right now, the SD card is working very well with the ESP32-S3 and FC11.

But...
Append a string[20] isn't practical, to save a text line.

For the component File (ESP32 SDMode) is a longer string possible?

Maybe 150, 200, or 512—would be better.

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[BenR]

Hello Stefan,

The string should be a pointer and so allow you to add your own string of any size. Try a bigger string and it should work, shout if it doesn't as it could be the "make a copy" parameter check box has been ticked by accident?

[stefan.erni]

Hi Ben

You're right...
long string are already ok.
I made a lot of test with the string write to the sd-card (no interrupt)
The test are here:

Sd_Card_MD_text_Copy.fcm

(4.43 KiB) Downloaded 4 times

And every test is working fine. PERFECT!

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But if I sample and save data, there is a problem with the long string.
On top I save short string 25 times. its ok.
On Botton I save a long string in one go. I get problem even if i use simulate the data but interrupt is on.

The result with short string is perfect.
but with the long string a lot of data is missing or wrong.

I'll see what I can do.

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[BenR]

Hello,

I think the problem may be doing the conversion to string inside the concatenate, there is a temporary string created to allow this but it is limited in size to 20 characters by default.

Try doing this instead to work around the problem.

.TempStr = ToString$(All_Data_Int[.count])
Save_Str = Save_Str + .TempStr
Save_Str = Save_Str + "\r\n"

[stefan.erni]

Hi Ben

It didn't help, even when I briefly disabled the IRQ.
But 25 short strings work fine.

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