Colibri vf50 not entering in recovery mode

I am working on colibri vf50 ( target for custom board ) with carrier board version 1.1A. I have two card Colibri Vf50 ( v1.1 A )modules. Both stopped booting from boot loader. I implemented the steps given on the following link number of times but not entering into recovery mode ( fails at association stage ).

VFxx Recovery Mode | Toradex Developer Center

Contents of vybrid_usb_work.conf

…/colibri-vf_bin/u-boot.imx:jump header

STEPS performed

linux@desktop# ./ -n -d /dev/ttyUSB0

Colibri VF rootfs detected
Put the module in recovery mode and press [ENTER]…

config file

parse vf_flash/vybrid_usb_work.conf

starting associating phase…

magic missmatch, response was 0x00000000

i had checked serial connection,they are properly connected.
Am i making some mistake…any help and pointers will be appreciated.!!!

What carrier board are you trying this on?

What BSP version did you try this with?

Please note that using our regular demo image packages no changes to e.g. vybrid_usb_work.conf whatsoever are required.

bsp version : - Colibri_VF_LinuxImageV2.5
carrier board : - iris v1.1A

i had just added (**…/colibri-vf_bin/**u-boot.imx:jump header) the path to u-boot.imx.
i do need to provide that right???

No, you really would not need to change anything on this at all but just proceed according to the following article on our developer website.

i also tested it with default vybrid_usb_work.conf but still no association …

yes i was missing this thing only thanks.

And you are absolutely sure your serial connection is proper? Please note that for the -n parameter to work right one would still need to additionally shorten RTS/CTS on the module side as indicated here. However if you are using a fully hand-shake enabled serial connection you would need to NOT specify the -n parameter to our script.