Content originally posted in LPCWare by snovik on Tue Sep 08 02:29:35 MST 2015 I'm using library LPCOpen. The datasheet contains support for MMC, but not shown in the library setting the buswidth for MMC. It only SD.
Content originally posted in LPCWare by laogan666 on Wed May 20 23:14:22 MST 2015 hello,i have a problem when i switch to 8 bit wide: I also have the code status = sdmmc_execute_command(pSDMMC, CMD_MMC_SWITCH, ((3<<24) | (183<<16) | (2<<8)), 0); But i can not read data correctly,the status back is 0x00002004,Did you have the same problem?
Content originally posted in LPCWare by frankeggink on Mon Nov 10 04:39:18 MST 2014 I'm able to read, write data to the micron emmc in 1 bit mode. I can also do this at 26 and 52 Mhz.
I've tried to switch the cards bus width with (CMD6) to 4 bit, but when i do that i get a DCDC error (data crc).
And when i change to 4bit mode (using CMD6) and then issue a (cmd8) to get the ecsd information. I get a (start bit error)
Content originally posted in LPCWare by wlamers on Fri Nov 07 03:38:09 MST 2014 Well as said above, write is about 7 MB/s, read 27 MB/s. Both with an 8 bit wide interface. I didn't do tests with a 4 and 1 bit interface. I think however that read speed wouldn't suffer much with a 4 bit interface. I didn't notice any problems with delays.
Content originally posted in LPCWare by frankeggink on Fri Nov 07 02:43:50 MST 2014 Hello,
The LPC4337 doesn't differ much from the LPC4357, i'm using a smaller chip size (144 pins) and only have 4 bit sdmmc. I'm also using a micron emmc chip (similar to the one you are using). Could you tell me how fast you can write to the chip. (in 1 bit, 4 bit and 8 bit mode)? Did you have any problems with delays between command send to the emmc chip?
Content originally posted in LPCWare by schisanoa on Mon Jul 07 08:34:32 MST 2014 Quote: wlamers eMMC is possible, even with the 8 bit interface. Performance depends mostly on the eMMC itself. I achive 27 MB/s read, and 7 MB/s write speeds with a Micron eMMC.
Content originally posted in LPCWare by schisanoa on Mon Jul 07 03:32:22 MST 2014 About the eMMC attention to the version because in the latest version JEDEC removed the SPI interface.
Content originally posted in LPCWare by wlamers on Mon Jul 07 03:27:36 MST 2014 eMMC is possible, even with the 8 bit interface. Performance depends mostly on the eMMC itself. I achive 27 MB/s read, and 7 MB/s write speeds with a Micron eMMC.
Content originally posted in LPCWare by bavarian on Fri Jul 04 07:37:58 MST 2014 It doesn't support NAND flashes with a dedicated interface. That's more the type of memories used in the application processor world (ARM9, Cortex-A). But you could realize a NAND interface with a combination of hardware and software. eMMC is based on MMC and this is supported by the SD card interface or standard SPI interface.