> - send_command() should be prefixed with sd_send_command() to avoid > potential collision
Your right, I didn't notice this. What if I need to read these values ? I don't understand the > following loop: > > if sd_byte_count == 0 then -- beginning of sector read > while spi_master != 0xFE loop -- wait till data is ready to read > end loop > end if > > Basically this is why my sample doesn't work, commenting the "while" loop > fixes the issue. Before a sector is ready to read, you should get one 0xFE. Sector size is almost always 512 on hard disks and sd cards. After a sector read, there are two CRC bytes. Yes, you should read in 512 byte chunks and must write in 512 byte chunks. I think some sd cards do support byte by byte reads/writes. I have not looked into it. I guess this method was chosen for speed of PC's, and smaller addressing. Matt. -- You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/jallib?hl=en.
