Bits within bytes have a defined order when you do things like pushing the CPU flags register to memory, reading it back into a numerical register, and then bit

Bits within bytes have a defined order when you do things like pushing the CPU flags register to memory, reading it back into a numerical register, and then bit-shifting/rotating through it. That's something you can do on basically any architecture that supports preemptive scheduling; there's usually either a PUSHF or PUSHALL there to assist. But, even without the ability to address the memory at the bit level, bits-within-bytes ordering still matters on any architecture where bits are striped between memory channels, RAID-0 wise. (Just like those graphics bitplanes!) The processor being LSB-first vs. MSB-first on how it interprets the data bus, determines which sockets you put the LoROM and HiROM firmware chips into your Apple II :)