PCIe chaining dma example test failed

Hi All:

I used PCI express compiler 7.2 in my porject with quartus II 7.2. The PCI Express MegaWizard auto generated two examples:chaining dma and simple dma.

I simulated the chaining dma example with runtb.bat in \chaining_dma\testbench. After standard DMA read(data is transferred from BFM shared memory to ep memory) and DMA write(data is transferred back from ep mem to the BFM shared mem) test,the testbench failed in data integrity check. It's reported that the write data not equal with read data. I found all of the DMA write data in the BFM shared mem are zero.

Any suggestion?

Thanks.

-huzj_ecc