MMC/ SD, sleep and wake up- Minimizing Current?

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Hi

Can someone please tell me how to put the MMC/ SD card into sleep (or is it idle?) mode, and then wake it up and resume writting blocks of data after where the last write occured?

I am trying to save on battery power during writting to the MMC/ SD cards.

Thank you in advance.
a.

[Ttelmah]

You need to read the data sheet for the card you are using. In SPI mode, most MMC cards, only support 'sleep' mode, not idle mode (Idle is a protocol state, not an electrical state). Sleep mode is usually entered automatically, if a command is not received for a short period (5mSec for the SanDisk cards), and wake-up, is also automatic.

Best Wishes

[ploana]

Ttelmah is right if a command is not received for a short period 5ms the sandisk card entered in sleep mode automatic.

for the use of a mmc/sd card you have to inititlize the card, and when you use the card in spi mode, you have to put the card in spi mode(but you have to write the checksumm by yourself, when you are not yet in spi mode).

best wishes

[arrow]

Hi

Thank you for your responses.

I have read the SD specifications, and they suggest that:

[Ttelmah]

The clock is only generated, when you send something. The clock stops when you stop sending commands/data to the unit.

Best Wishes