Source code (FAT16) and PCB for interfaceing PIC to MMC/SD cards available here: http://www.compsys1.com/workbench/On_top_of_the_Bench/MMC_Project/mmc_pr oject.html Also has a PCB for Atmel AVR and MMC/SD card. Nice site! Tom Deutschman www.wizbangdesigns.com > -----Original Message----- > From: pic microcontroller discussion list > [mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Gordon Williams > Sent: Friday, January 16, 2004 5:05 AM > To: PICLIST@MITVMA.MIT.EDU > Subject: Re: [OT:] Help MMC SPI Mode > > > Hi, > > I'm going to be going through the same thing in about a > week's time. I'm putting together the schematic now for a > data logger. For my reference I am using the Multimedia Card > Product Manual from Sandisk. It is on there website. It > appears to be quite comprehensive. > > Gordon Williams > Ottawa, Canada > > ----- Original Message ----- > From: "#LEE CHUN YONG#" > To: > Sent: Friday, January 16, 2004 7:26 AM > Subject: [OT:] Help MMC SPI Mode > > > Currently I am using the MMC card in SPI mode. I would like > to know more about the command, write and response sequence > of the writing of 1 block of data. The block size of 512 byte > is used. So I will start the writing process with write block > command(CMD24). After that I will try to get the response > from the MMC card( I did get bit string of '0000 0000'). > After that I would output 10 clocks to MMC card. Then I will > start to output start byte( bit string of '1111 1110' ). > Subsequently, I will write 512 bytes of data. Then I just > write 2 bytes of dummy byte as the CRC. Since I didn't turn > on the CRC feature of the MMC card, any 2 bytes of dummy data > will be fine. After sending the 2 bytes of CRC, I should > immediately get bit string of 'xxx0 0101' as the data > response. Are my procedures correct? Thank you in advance and > have a nice day! > > > > -- > http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu