01-10-2016, 03:59 AM
(01-09-2016, 06:52 AM)Andrew2 Wrote:(01-09-2016, 03:10 AM)joe Wrote: answer me proof sd card speed ! Please !
Nice, you seem to be the average Pine64 kickstarter backer trusting in specs and promises more than in reality
(01-08-2016, 03:31 PM)baylf2000 Wrote: Getting anything greater than about 25MB/s from an SD card
I would suspect it's more close to 20/22MB/s (write/read) as with any other Allwinner SoC now.
Exactly. But it's not just Allwinner. The SD card specs say clearly that the maximum theoretical speed for the SD bus itself is 25MB/s. The only way to improve on that is to upgrade the bus to UHS, which requires specialised voltages in the case of UHS I, and extra data lines in the case of UHS II.
I have never seen an ARM soc board implement a UHS interface. I have no idea why. I wish I knew. It's not rocket science. I'm not it might be because of licensing costs for UHS interfaces, but no manufacturer has ever confirmed this to me.
For our rude Chinese friend, here is the official interface specs from the SD Association themselves. https://www.sdcard.org/developers/overvi...index.html
