Filename encoding issue

[glennjones]

Hi,

I am trying out the example sd-card code and the file writes to the sd-card, but the file name is encoded incorrectly. This means I can not read it back again and get the error.

/app/microsd.js:19: attempt to index local 'data' (a nil value)

[johnnyman727]

Hey Glen, thanks for reporting this. It may or not be the same issue that others have been reporting which I encapsulated in #18. @natevw is going to look into it.

[natevw]

This is indeed very likely due to an encoding trouble. I've more directly isolated a problem using the struct-fu test suite which is failing on Tessel again — that library is used by sdcard and fatfs for reading and writing binary fields.

Filed tessel/t1-runtime#690 — the firmware recently got some improved support for Buffer encoding but one spot was missed. I'll work with the TM folks to get a fix out and/or keep struct-fu working with the new situation.

Local workaround

You can work around temporarily by changing this line in your project's "node_modules/sdcard/node_modules/fatfs/node_modules/struct-fu/lib.js":

if (Buffer("\ud83c\udf91", 'utf16le')[0] !== 0x3c) require("./_workaround_tessel_358.js");

to:

if (1 || Buffer("\ud83c\udf91", 'utf16le')[0] !== 0x3c) require("./_workaround_tessel_358.js");

[glennjones]

Thanks Nathan, your workaround sorted out the issue for me.

[natevw]

Tessel now has built-in support for the utf16le buffer encoding (tessel/t1-runtime#645) and so this issue is likely resolved. (IIRC struct-fu also got an interim fix for this.) Thanks for your original report!