Q: The old EVAL-ADXL345Z-DB can work well, why some new board cannot save data on the SD card? Even for the old EVAL-ADXL345Z-DB, after changing SD card, the data cannot be save too.
A: This is because the firmware is developed based on a specific SD card vendor and that 2G SD card is obsolete. When changing to other microSD card or SDHC card, the firmware encounter the compatibility issue. To solve this problem, the firmware is updated to support all kinds of 2G, 8G, 16G, 32G SD card. Attached is the updated firmware, please try to download it to the MCU ADUC7024. Refer to how to download and the corresponding software are attached also.
For all the EVBs that shipped since Oct 19th, 2017, the firmware is updated already and the end user do not need to download the attached .hex again.
For the users that do not have the SD card compatibility issue, the firmware update is not necessary too.