In SPI mode, a CRC is only required for the reset (CMD0) command, which initializes the card in SPI mode. By default, CRC is disabled in SPI mode, and a dummy CRC byte (byte 6 of 6 in each command) of FFh is sent with each command. Cheers, Ishaan ----- Original Message ----- From: "Tom" To: Sent: Tuesday, July 29, 2003 13:28 Subject: Re: [PIC]: Puzzling MMC read failure > You don't mention sending a crc; isn't one required? > > Tom M. > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body