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It is needed e.g. by Atmel MXT touch controller. I spent a lot > of time debugging the race conditions in the XIIC, which I ultimately > fixed (the patches are upstream), but the long transfers I rather > fixed in the MXT driver instead. > > I also recall there was supposed to be some update for the XIIC core > coming with newer vivado, but I might be wrong about that. It seems to be the other way around - dynamic mode is limited to 255 bytes - when you trigger dynamic mode you first write the address of the slave to the FIFO, then you write the length as one byte so you can't request more than 255 bytes. So *standard* mode is used for those messages. In other words - dynamic mode is the one that is more limited - everything that you can do in dynamic mode you can also do in standard mode. So why don't we use standard mode always for everything? Krzysztof