sd_wr_state.vhd

SD卡读卡器模块的VHDL及软件驱动代码

package sd_wr_state is
	type SD_WR_STAT is
	(
		SD_WR_INIT, -- initialize
		
		SD_WR_IDLE, -- ready to process any command
		
		-- init card
		SD_WR_PRE_WAIT_PWRUP, -- load 80 into counter
		SD_WR_WAIT_PWRUP, -- wait 80 cycle for power up of the card
		SD_WR_SEND_CMD0, -- send cmd0 to reset the card
		
		-- init loop
		SD_WR_PRE_WAIT_READY, -- load 127 into counter
		SD_WR_WAIT_READY, -- wait 127 cycle
		SD_WR_SEND_CMD55, -- indicates that the next command is an app_cmmd
		SD_WR_RECV_R1_TO_CMD55, -- receive R1 to cmd55
		SD_WR_SEND_ACMD41, -- asks card to send its OCR
		SD_WR_RECV_R3_TO_ACMD41, -- receive OCR
		
		-- continue init
		SD_WR_SEND_CMD2, -- asks card to send CID
		SD_WR_RECV_R2_TO_CMD2, -- receive CID
		SD_WR_SEND_CMD3, -- asks the card to publish a new RCA
		SD_WR_RECV_R6_TO_CMD3, -- receive RCA
		SD_WR_RECORD_RCA, -- record RCA
		SD_WR_SEND_CMD9, -- Addressed card sends its CSD
		SD_WR_RECV_R2_TO_CMD9, -- receive CSD
		SD_WR_SEND_CMD7, -- select the card
		SD_WR_RECV_R1_TO_CMD7, -- receive R1 to cmd7
		
		-- set 4 line mode
		SD_WR_SEND_CMD55_2, -- indicates that the next command is an app_cmmd
		SD_WR_RECV_R1_TO_CMD55_2, -- receive R1 to cmd55
		SD_WR_SEND_ACMD6, -- set 4 line mode
		SD_WR_RECV_R1_TO_ACMD6, -- receive R1 to acmd6
		
		-- set block length
		SD_WR_SEND_CMD16, -- Selects a block length
		SD_WR_RECV_R1_TO_CMD16, -- receive R1 to cmd16
		
		-- init finished
		SD_WR_INIT_FAILED, -- initialize failed
		SD_WR_INIT_SUCCESS, -- initialize success
		
		-- start read
		SD_WR_CLEAR_BUFFER, -- discard received data
		
		-- read single block
		SD_WR_SEND_CMD17, -- read a block
		SD_WR_RECV_DATA, -- receive the block
		
		-- read multiple block
		SD_WR_REC_ADDR,	-- record section address
		SD_WR_SEND_CMD18, -- start streaming read
		SD_WR_STRRECV_DATA, -- receive stream
		SD_WR_INC_ADDR,	-- increase section address
		SD_WR_SEND_CMD12, -- stop streaming read
		SD_WR_RECV_R1b_TO_CMD12, -- receive R1b to cmd12
		SD_WR_STRRECV_PAUSE -- streaming read was paused
	);
end sd_wr_state;