不能连续擦除Flash sector

我在C:\ti\controlSUITE\device_support\f28m35x\v207\F28M35x_examples_Dual\flash_prog\m3 的示例代码中加入下面一段代码，发现不能连续的擦写sector,有时候能连续的擦除两三个sector，有时候不能，总是在Fapi_doBlankCheck报出错，参考过e2e上两个回复，

e2e.ti.com/.../1233117

e2e.ti.com/.../1204541

按照提示添加了设置：

*(int *)0x400FA160 = 0xC12F59A0;
FlashInit();

oLibInfo = Fapi_getLibraryInfo();
Fapi_setupBankSectorEnable();

都是一样，不能做连续擦除，添加代码如下：

uint32 sectorstart,num;

uint32 sectorlength;
sectorstart=0x00230000;
sectorlength=0;
for(num=6;num<oFlashBankSectors.u32NumberOfSectors;num++)
{
if(num>0)
{
sectorstart=sectorstart+sectorlength;
}
else
{sectorstart=oFlashBankSectors.u32BankStartAddress;}
sectorlength=((uint32)oFlashBankSectors.au8SectorSizes[num])*2048;
oReturnCheck = Fapi_issueAsyncCommandWithAddress(Fapi_EraseSector,
(uint32 *)sectorstart);
// Wait until FSM is done with erase sector operation
while (Fapi_checkFsmForReady() != Fapi_Status_FsmReady){}

oReturnCheck = Fapi_doBlankCheck((uint32 *)sectorstart,
sectorlength,
&oFlashStatusWord);
if(oReturnCheck != Fapi_Status_Success)
{
//Example_Error(oReturnCheck);
}
}