What makes initialize return !11 in alfat oem board?

I’m making data logger and the data are saved in usb via alfat oem board. But, after about 126 or 127 data, when the program tried to initialize USB on port 0, ALFAT return !11, and then the program retried and always !11.

is it problem that I always initialize USB that has been already initialized before?
if this is problem, why there’s no problem for 126 or 127 data (126 or 127 initialize)?

or maybe another problem?

can you list what makes initialize return !11?

thank you

@ kalkaneus -

0x11 means can not initialize that usb. If you are sure 5V is connected correctly then 99,9% reason causes this problem is the usb is not standard. Try to format or a different one.

  • Are you using ALFAT OEM or ALFAT USB board? If ALFAT OEM, the usb port 0 is the bottom one.
  • What kind / size of USB are you using?
  • What ALFAT firmware are you using?
  • What interface are you using? SPI / UART / I2C?

What does that mean, please?

  1. ALFAT OEM, already put flash disk in bottom one
  2. Sandisk 4GB
  3. v1.0.8
  4. SPI

I succeeded initialize USB for 126 or 127 times (usually 127 times). After that, when I want to initialize again, ALFAT return !11.

@ kalkaneus -

try to reset the ALFAT board and add a delay between each times.

1 Like