Altera cyclone V Technical Reference page 991

cv_5v4
2016.10.28
• Bit[31:12] = 0x0 (reserved bits)
• Bit[11:8] = 0x1 (supply voltage value)
• Bit[7:0] = 0xAA (preferred check pattern by SD memory cards compliant with SDIO Simplified
Specification Version 2.00 and later.)
Refer to SDIO Simplified Specification Version 2.00 as described on the SD Association website.
• If a response is received to the previous SEND_IF_COND command, the card supports SD High-
Capacity, compliant with SD Specifications, Part 1, Physical Layer Simplified Specification Version
2.00.
• If no response is received, proceed to
2. Send the SD_SEND_OP_COND (ACMD41) command with the following arguments:
• Bit[31] = 0x0 (reserved bits)
• Bit[30] = 0x1 (high capacity status)
• Bit[29:25] = 0x0 (reserved bits)
• Bit[24] = 0x1 (S18R --supports voltage switching for 1.8V)
• Bit[23:0] = supported voltage range
• If the previous SD_SEND_OP_COND command receives a response, then the card type is SDHC.
Otherwise, the card is MMC or CE-ATA. In either case, skip the following steps and proceed to
5 of the "Identifying the Connected Card Type" section.
• If the initial SEND_IF_COND command does not receive a response, then the card does not
support High Capacity SD2.0. Now, proceed to
3. Next, issue the GO_IDLE_STATE command followed by the SD_SEND_OP_COND command with
the following arguments:
• Bit[31] = 0x0 (reserved bits)
• Bit[30] = 0x0 (high capacity status)
• Bit[29:24] = 0x0 (reserved bits)
• Bit[23:0] = supported voltage range
If a response is received to the previous SD_SEND_OP_COND command, the card is SD type.
Otherwise, the card is MMC or CE-ATA.
Note: You must issue the SEND_IF_COND command prior to the first SD_SEND_OP_COND
command, to initialize the High Capacity SD memory card. The card returns busy as a response
to the SD_SEND_OP_COND command when any of the following conditions are true:
• The card executes its internal initialization process.
• A SEND_IF_COND command is not issued before the SD_SEND_OP_COND command.
• The ACMD41 command is issued. In the command argument, the Host Capacity Support
Determine if Card is a CE-ATA 1.1, CE-ATA 1.0, or MMC Device
Use the following sequence to determine whether the card is a CE-ATA 1.1, CE-ATA 1.0, or MMC device:
Determine whether the card is a CE-ATA v1.1 card device by attempting to select ATA mode.
1. Send the SD/SDIO SEND_IF_COND command, querying byte 504 (S_CMD_SET) of the EXT_CSD
register block in the external card.
SD/MMC Controller
Send Feedback
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(HCS) bit is set to 0, for a high capacity SD card.
Determine if Card is a CE-ATA 1.1, CE-ATA 1.0, or MMC Device
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the next decision statement.
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step step 3.
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step
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