… became much easier to make further U-Boot progress because I could send new changes through minicom using YMODEM and write them to the SD card, rather than constantly moving the SD card back and forth between the Chumby and my USB card reader
Can someone explain this? I have worked porting mainline kernel to e-readers and game consoles and I just put up with a lot of SD card swapping until I get something somewhat stable. Would love to optimise that.
but IMO ymodem is a royal pain (takes forever) unless your baud gets reasonably high (over 3M is nice). More traditional ways or transferring files include usb or ethernet, but those might not be available. You can also use JTAG, which tends to be a bit faster than serial, but still too slow for e.g. a bigger rootfs.
Can someone explain this? I have worked porting mainline kernel to e-readers and game consoles and I just put up with a lot of SD card swapping until I get something somewhat stable. Would love to optimise that.
https://u-boot.readthedocs.io/en/latest/usage/cmd/loady.html
but IMO ymodem is a royal pain (takes forever) unless your baud gets reasonably high (over 3M is nice). More traditional ways or transferring files include usb or ethernet, but those might not be available. You can also use JTAG, which tends to be a bit faster than serial, but still too slow for e.g. a bigger rootfs.