Also, if the active bank fails to boot 3 times in a row (e.g. power cut during flashing, corrupted download), no active bank switch occurs.
This “dual bank” setup so provides a simple rollback feature: if the upgrade fails (eg. The process of switching active bank is called “switchover”. On success, the active bank gets switched to the former passive one. During a firmware upgrade, the new image gets flashed into the “passive” bank directly from a network download stream. You can switch the active bank to the second bank_2 and get the stock bootloader attempt to boot that one by default. On a brand new device, only the first bank_1 contains a firmware. When the flash chip is large enough, two firmware images (kernel+rootfs) can be kept flashed on the chip, and the bootloader automatically attempts to boot the “active bank” first. Each of them do only accept flashing its own firmware images as long as the stock bootloader is in place. Other than this, testing so far indicates that the PCB layout is identical for all boards. The only hardware difference seems to be flash chip, which is either 8 MiB or 16 MiB depending on whether the device supports “dual bank” setup or not. The TG582n comes in at least three distinct hardware variants distinguished by their board name (DANT-1, DANT-T, DANT-V).
0 kommentar(er)
