AM3358: how to config u-boot for UART boot

Part Number: AM3358

Hello

Just want to know whether to have different uboot def_config

I have used

am335x_boneblackstty -F /dev/ttyUSB0 115200 cs8 -parenb -cstopb -ixoff

but I had timeout in ACK eve after correct setting  wth cmd below

stty -F /dev/ttyUSB0 115200 cs8 -parenb -cstopb -ixoff

So I'm wondering if any special uboot def_config for UART boot

OR

what should to do in case ACK timeout ??

Thnx

DuyKy

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