vincenzo genovese

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11 years, 5 months ago.

Problems while using semihost_powerdown() on LPC11U24

Good Morning. The problem is: if I try to utilize the function semihost_powerdown() while the system is battery powered then there is no way save data on local memory.

What can I do?

Best Regards

2 Answers

Wim Huiskamp
11 years, 5 months ago.

You could use a dedicated local memory for the LPC11U24 (I2C or SPI EEPROM; SPI to SD Card). You can also try to power up I/F chip before file I/O and then power down again when you are done.

Thanks a lot for prompt the reply. Please, could you point out the functions you use to power up/down the I/F chip?

Best regards Vincenzo

posted by vincenzo genovese 06 Nov 2012
Wim Huiskamp
11 years, 5 months ago.

There is more info here http://mbed.org/handbook/Beta and here http://mbed.org/forum/bugs-suggestions/topic/434/?page=1#comment-14029

Quick read suggests that you may not be able to wake up the interface chip again after powerdown unless the power is cycled. That would make it hard to use for your purpose. In that case a dedicated SD card or EEPROM would be the best option.