CMSIS-Driver  Version 2.00
Peripheral Interface for Middleware and Application Code
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MCI Bus Speed Mode Values

Specify the bus speed mode. More...

Macros

#define ARM_MCI_BUS_DEFAULT_SPEED   (0x00)
 SD/MMC: Default Speed mode up to 25/26MHz.
 
#define ARM_MCI_BUS_HIGH_SPEED   (0x01)
 SD/MMC: High Speed mode up to 50/52MHz.
 
#define ARM_MCI_BUS_UHS_SDR12   (0x02)
 SD: SDR12 (Single Data Rate) up to 25MHz, 12.5MB/s: UHS-I (Ultra High Speed) 1.8V signaling.
 
#define ARM_MCI_BUS_UHS_SDR25   (0x03)
 SD: SDR25 (Single Data Rate) up to 50MHz, 25 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.
 
#define ARM_MCI_BUS_UHS_SDR50   (0x04)
 SD: SDR50 (Single Data Rate) up to 100MHz, 50 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.
 
#define ARM_MCI_BUS_UHS_SDR104   (0x05)
 SD: SDR104 (Single Data Rate) up to 208MHz, 104 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.
 
#define ARM_MCI_BUS_UHS_DDR50   (0x06)
 SD: DDR50 (Dual Data Rate) up to 50MHz, 50 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.
 

Description

Specify the bus speed mode.

The function ARM_MCI_Control with control = ARM_MCI_BUS_SPEED configures the bus speed of the MCI to the requested bits/s specified with arg.

The function ARM_MCI_Control with control = ARM_MCI_BUS_SPEED_MODE configures additional the bus speed mode of the MCI as specified with arg.

The function ARM_MCI_GetCapabilities lists the supported bus signaling voltage. Initially, all SD card families use a 3.3 volt electrical interface. Some SD cards can switch to 1.8 volt operation. For example, the use of ultra-high-speed (UHS) SD cards requires 1.8 volt operation and a 4-bit bus data width. The bitfield ARM_MCI_CAPABILITIES.signaling_1v8 encodes whether the driver supports 1.8 volt signaling.

See Also
Note
The controls are not available when the SPI mode is used.

The following modes are supported:

Macro Definition Documentation

#define ARM_MCI_BUS_DEFAULT_SPEED   (0x00)

SD/MMC: Default Speed mode up to 25/26MHz.

See Also
ARM_MCI_Control;
#define ARM_MCI_BUS_HIGH_SPEED   (0x01)

SD/MMC: High Speed mode up to 50/52MHz.

See Also
ARM_MCI_Control;
#define ARM_MCI_BUS_UHS_DDR50   (0x06)

SD: DDR50 (Dual Data Rate) up to 50MHz, 50 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.

See Also
ARM_MCI_Control;
#define ARM_MCI_BUS_UHS_SDR104   (0x05)

SD: SDR104 (Single Data Rate) up to 208MHz, 104 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.

See Also
ARM_MCI_Control;
#define ARM_MCI_BUS_UHS_SDR12   (0x02)

SD: SDR12 (Single Data Rate) up to 25MHz, 12.5MB/s: UHS-I (Ultra High Speed) 1.8V signaling.

See Also
ARM_MCI_Control;
#define ARM_MCI_BUS_UHS_SDR25   (0x03)

SD: SDR25 (Single Data Rate) up to 50MHz, 25 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.

See Also
ARM_MCI_Control;
#define ARM_MCI_BUS_UHS_SDR50   (0x04)

SD: SDR50 (Single Data Rate) up to 100MHz, 50 MB/s: UHS-I (Ultra High Speed) 1.8V signaling.

See Also
ARM_MCI_Control;