LAUNCHXL-CC1352R1: NVS_write 是否無法部分erase?

sdk:simplelink_cc13xx_cc26xx_sdk_6_10_00_29

請問使用NVS_write是否無法部分erase?

我的buffer是uint8_t[16], 但我只想要寫入前面4個byte, 所以bufferSize = 4, flag = NVS_WRITE_ERASE | NVS_WRITE_POST_VERIFY

int_fast16_t status = NVS_write(nvsHandle, 0, (void *) buffer, 4,
                                             NVS_WRITE_ERASE | NVS_WRITE_POST_VERIFY);

但我發現前面4個byte確實有寫入成功, 但是其他12個byte全部被erase了.

請問這是正確的嗎? 我原本以為只有要寫入的byte會erase而已

 *  @param   buffer     A buffer containing data to write to
 *                      the NVS region.
 *
 *  @param   bufferSize The size of the buffer (number of bytes to write).
 *
 *  @param   flags      Write flags (#NVS_WRITE_ERASE, #NVS_WRITE_PRE_VERIFY,
 *                      #NVS_WRITE_POST_VERIFY).

extern int_fast16_t NVS_write(NVS_Handle handle, size_t offset, void *buffer,
                     size_t bufferSize, uint_fast16_t flags);

Nick Sun：

您好，

收到您的问题了，我们升级到英文论坛给工程师看下，有答复尽快给到您。

,

Nick Sun：

您好，

从NVS driver的文档中，我们可以看到如下内容：

"Erase write flag.

If NVS_WRITE_ERASE is set in the flags passed to NVS_write(), the affected destination flash sectors will be erased prior to the start of the write operation."

这意味着这将擦除整个部分，而不仅仅是您要写入的字节。

具体信息您可以参考：NVS.h File Reference

您还可以参考 NVSCC26XX.c file中的代码：

/* If erase is set, erase destination sector(s) first */
if (flags & NVS_WRITE_ERASE)
{size = bufferSize & sectorBaseMask;if (bufferSize & (~sectorBaseMask)){size += sectorSize;}retval = doErase(handle, offset & sectorBaseMask, size);if (retval != NVS_STATUS_SUCCESS){SemaphoreP_post(writeSem);return (retval);}
}

希望能够帮助到您。