On 30/08/2011 17.56, M.L. wrote: > On Tue, Aug 30, 2011 at 9:40 AM, Nicola Perotto = wrote: >> I was not able to write at more than 64KB/s, continuous. >> The problem, I think, is that we write the internal SD buffer at full sp= eed and >> then we must wait the real write! With only 2*512 byte buffer this is a = bootleneck. >> > The problem with all embedded devices using SD cards is that we are > using them in SPI mode which almost never works according to the way > they say it should. And SPI mode is very very slow compared to 4-bit > wide bus that real controllers can use. > I think that is only an half of the problem: the SD card controller (inside= the=20 card) write the data with his own rules and different card has different ru= les. The buffering is in most cases more important that transfer speed! --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .