Broadcom BCM2835

E 1 for cmd18 and cmd25 and 0 for cmd17 and cmd24

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Unformatted text preview: ex as command: 0 = disabled 1 = enabled Check the responses CRC: 0 = disabled 1 = enabled Reserved - Write as 0, read as don't care CMD_RSPNS_TYPE Type of expected response from card: 00 = no response 01 = 136 bits response 10 = 48 bits response 11 = 48 bits response using busy RW 0x0 RW RW 0x0 0x0 Type Reset Bit(s) 31:30 29:24 23:22 Field Name 21 CMD_ISDATA RW 0x0 20 CMD_IXCHK_EN RW 0x0 19 CMD_CRCCHK_EN RW 0x0 18 17:16 06 February 2012 Broadcom Europe Ltd. 406 Science Park Milton Road Cambridge CB4 0WW 2012 Broadcom Corporation. All rights reserved Page 69 15:6 5 TM_MULTI_BLOCK Reserved - Write as 0, read as don't care Type of data transfer 0 = single block 1 = multiple block Direction of data transfer: 0 = from host to card 1 = from card to host Select the command to be send after completion of a data transfer: 00 = no command 01 = command CMD12 10 = command CMD23 11 = reserved Enable the block counter for multiple block transfers: 0 = disabled 1 = enabled Reserved - Write as 0, read as don't care RW 0x0 4 TM_DAT_DIR RW 0x0 3:2 TM_AUTO_CMD_EN RW 0x0 1 TM_BLKCNT_EN RW 0x0 0 RESP0 Register Synopsis This register contains the status bits of the SD card s response. In case of commands CMD2 and CMD10 it contains CID[31:0] and in case of command CMD9 it contains CSD[31:0]. Note: this register is only valid once the last command has completed and no new command was issued. Description Bits 31:0 of the card s response Type RW Reset 0x0 Bit(s) 31:0 Field Name RESPONSE RESP1 Register Synopsis In case of commands CMD2 and CMD10 this register contains CID[63:32] and in case of command CMD9 it contains CSD[63:32]. Note: this register is only valid once the last command has completed and no new command was issued. 06 February 2012 Broadcom Europe Ltd. 406 Science Park Milton Road Cambridge CB4 0WW 2012 Broadcom Corporation. All rights reserved Page 70 Bit(s) 31:0 Field Name RESPONSE Description Bits 63:32 of the card s response Type RW Reset 0x0 RESP2 Register Synopsis In case of commands CMD2 and CMD10 this register contains CID[95:64] and in case of command CMD9 it contains CSD[95:64]. Note: this register is only valid once the last command has completed and no new command was issued. Description Bits 95:64 of the card s response Type RW Reset 0x0 Bit(s) 31:0 Field Name RESPONSE RESP3 Register Synopsis In case of commands CMD2 and CMD10 this register contains CID[127:96] and in case of command CMD9 it contains CSD[127:96]. Note: this register is only valid once the last command has completed and no new command was issued. Description Bits 127:96 of the card s response Type RW Reset 0x0 Bit(s) 31:0 Field Name RESPONSE DATA Register Synopsis This register is used to transfer data to/from the card. Bit 1 of the INTERRUPT register can be used to check if data is available. For paced DMA transfers the high active signal dma_req can be used. Description Data to/from the card Type RW Reset 0x0 Bit(s) 31:0 Field Name DATA 06 February 2012 Broadcom Europe Ltd. 406 Science Park Milton Road Cambridge CB4 0WW 2012 Broadcom Corporation. All rights reserved Page 71 STATUS Register Synopsis This register contains information intended for debugging. Its values change automatically according to the hardware. As it involves resynchronisation between different clock domains it changes only after some latency and it is easy sample the values too early. Therefore it is not recommended to use this register for polling. Instead use the INTERRUPT register which implements a handshake mechanism which makes it impossible to miss a change when polling. Description Reserved - Write as 0, read as don't care DAT_LEVEL1 CMD_LEVEL DAT_LEVEL0 Value of data lines DAT7 to DAT4 Value of command line CMD Value of data lines DAT3 to DAT0 Reserved - Write as 0, read as don't care READ_TRANSFER New data can be read from EMMC: 0 = no 1 = yes New data can be written to EMMC: 0 = no 1 = yes Reserved - Write as 0, read as don't care DAT_ACTIVE At least one data line is active: 0 = no 1 = yes Data lines still used by previous data transfer: 0 = no 1 = yes Command line still used by previous command: 0 = no 1 = yes RW 0x0 RW 0x0 RW RW RW 0xf 0x1 0xf Type Reset Bit(s) 31:29 28:25 24 23:20 19:10 9 Field Name 8 WRITE_TRANSFER RW 0x0 7:3 2 1 DAT_INHIBIT RW 0x0 0 CMD_INHIBIT RW 0x0 06 February 2012 Broadcom Europe Ltd. 406 Science Park Milton Road Cambridge CB4 0WW 2012 Broadcom Corporation. All rights reserved Page 72 CONTROL0 Register Synopsis This register is used to configure the EMMC module. For the exact details please refer to the Arasan documentation SD3.0_Host_AHB_eMMC4.4_Usersguide_ver5.9_jan11_10.pdf. Bits marked as reserved in this document but not by the Arasan documentation refer to functionality which has been disabled due to the changes listed in the previous chapter. Description Reserved - Write as 0, read as don't care ALT_BOOT_EN Enable alternate boot mode access: 0 = disabled 1 = enabled Boot mode access: 0 = stop boot mode access 1 = start boot mode access SPI mode enable: 0 = normal mode 1 = SPI mode Enable SDIO interrupt at block gap (only valid if the HCTL_DWIDTH bit is set): 0 = disabled 1 = enabled Use DAT2 read-wait protocol for SDIO cards supporting this: 0 = disabled 1 = enabled Restart a transaction which was stopped using the GAP_STOP bit: 0 = ignore 1 = restart Stop the current transaction at the next block gap: 0 =...
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This note was uploaded on 04/17/2013 for the course EEC 193 taught by Professor Kevin during the Spring '13 term at UC Davis.

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