ok so the a20 board's nand ic is recognised in software... but *not* by the eGON bootloader ROM: it's too modern. i'm going to have to find an older (lower-capacity) TSSOP-48 NAND IC. arse.
the rk3288 board is *almost* up: the i2c bus for the PMICs appears to be non-operational (reason yet to be determined but most likely to be a short-circuit) which, when the linux kernel tries to initialise each of the PMICs hangs on accessing the I2C bus. when i replaced the I2C pullup resistors with 1.5k instead of 2.2k then SD/MMC refused to boot! only thing i can think of is, the short is pulling the 3.3v power rail down enough to affect the SD/MMC. i'll keep investigating.
l.
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