[U-Boot] PR1-Appliance UART Boot Issue

[Amber and Sarosh]

Hi all We have somehow damaged u-boot of PR1-Appliance. Now are trying to unbrick the device.We read in one of the posts at the switchfin forum   that we can unbrick the device by changing the Boot mode to UART.

Here are the steps that we are following to address this issue.
 
1. Changing the bootmode to UART 2. Loading the u-boot  file in ldr format through LdrViewer. 
3.  Accessing this u-boot in hyperterminal via serial connection
4. Transfering the u-boot file for SPI mode in ldr format to the board via tftp to a RAM location.
5. Writing this u-boot to the SPI flash using sf commands of erase and write.
6.Changing the bootmode to SPI again.
7. Trying to access this u-boot from SPI flash .
 
In these setps, the u-boot  files that are accesed successfully in both UART and SPI boot modes are the ones compiled for BF537 STAMP board on the terminal emulator. This uboot is unable to boot a uImage compiled for PR1-Appliance. The ones  we compiled for PR1 Appliance dont show up on the terminal emulator in both modes, and same is the result for the precompiled u-boot for PR1 Appliance. 
Can anyone please guide us, what to do in order to access u-boot of PR1-Appliance and to boot the image?
Let us know if you require any other details.We shall be very thankful!
 
Regards,
Amber & Sarosh