[jareklupinski]

that's true! 0xAA 0x55 would work to differentiate that case?

[MadnessASAP]

Yes, AA and 55 are common test patterns for a variety of hardware.

Haven't seen A5 in the wild but I suppose it could be useful as a initial "Let's setup a connection" where endianness is unknown. Assuming the next thing that is exchanged is an endian negotiation.

[genter]

I like to have several sequential ones. Easier to see on the oscilloscope. (I spent last night getting a microcontroller to talk to a SPI device, so I'm still licking my wounds.)

[theblazehen]

0xAA 0x55 is actually used as the last two bytes in the MBR just for this purpose