I use EXAR's XR16V554D to expand AT91SAM9261's uart, system is wince6.0.
Now the performance is: it can send out successfully, but it receive chars alwasy with wrong chars. For examples:
when pc send out: aaabbbcccdddeeefffggghhh
it receive: aaabbbcccdddeeefffggghhhcccccccccccccccccccccccccccccccccccccccccc(c's count is different, sometimes several, sometimes some tens of. )
or aaabbbcccdddeeefaaaaaaaaaaaaaaaaaaaaaaffggghhhccccccccccccccccc
......

PC send out: 1112222wwww4444555556666
it receive: 1112222wwww4444555556666wwwwwwwwwwwwwwwwwwww or 1112222wwww44446666666666666555556666
......

Someone said it is because of 9261's smc timing setup is wrong for 16C554, but I changed it many times, the result is same, can not receive correctly.

Here is one of my setting for 16c554, (I tried deifferent setting, i did not define TDF, for I don't know where TDF is used.)
AT91SAM926x_SetChipSelectTimingIn_ns( pSMC, // pSMC
0, // Chip Select
GetMasterClock(FALSE),
AT91C_DM9000_NWE_SETUP, // dwNWE_SETUP
AT91C_DM9000_NCS_WR_SETUP,// dwNCS_WR_SETUP
0, // dwNRD_SETUP
20, // dwNCS_RD_SETUP
AT91C_DM9000_NWE_PULSE, // dwNWE_PULSE
AT91C_DM9000_NCS_WR_PULSE, // dwNCS_WR_PULSE
140, // dwNRD_PULSE
100, // dwNCS_RD_PULSE
160, // dwNRD_CYCLE
AT91C_DM9000_NWE_CYCLE );// dwNWE_CYCLE

please help me.

thanks!