| In order to boot the AXP using the xmodem interface when the board fails |
| to boot and reaches the "trying uart" option in the BootROM, you need to |
| follow the follwing steps: |
| |
| - Start the minicom and make sure the you can see the BootROM printings |
| that end with the line "BootROM: Trying UART" |
| - At this stage the board is ready to get a pattern that instructs it |
| what to do (either start Xmodem or go into a debug shell). |
| - To star the Xmodem simply send the "Xmodem_boot_pattern.bin" as ascii |
| (Ctrl+A then s, then select ascii). |
| - After sending the file, you should start seeing strange characters on |
| the screen printed once in a second. These are the Xmodem NACKs. |
| - This means that you are ready to send the new u-boot with Xmodem (which |
| needs to be with checksum packets and not crc-16 that is used in default |
| Xmodem in minicom). |
| - Compile the sx-at91.c file (or you can use my pre-built). |
| - Add this binary to the minicom transfer protocols (see instructions in |
| the file sx-at-91.c header). The newly added file should look like: |
| | J sx-at91 <path to sx-at91 file> <serial port> Y U N N N | |
| example: |
| | J sx-at91 /home/tawfik/temp/x/sx-at91 /dev/ttyS1 Y U N N N | |
| - Please note that you need to use the correct path and "tty" device. In my |
| example I have the board connected to /dev/ttyS1. |
| - Start the Xmodem transfer through sending the uart boot file |
| (u-boot-2009.08-2.3.2-uart.bin) and selecting the sx-at91 protocol (Ctrl+a |
| then s, select ax-at91) |
| - When the transfer finishes, press any key to go back and the u-boot |
| should be loaded. |