leon912 Posted February 3, 2016 Report Share Posted February 3, 2016 Hi, I'm trying to write data inside the sdram on the papilio pro board. To do so I downloaded the hamster's code where a SDRAM controller is implemented. However, I don't understand the input interface of that controller: -- Interface to issue reads or write data cmd_ready : out STD_LOGIC; -- '1' when a new command will be acted on cmd_enable : in STD_LOGIC; -- Set to '1' to issue new command (only acted on when cmd_read = '1') cmd_wr : in STD_LOGIC; -- Is this a write? cmd_address : in STD_LOGIC_VECTOR(sdram_address_width-2 downto 0); -- address to read/write cmd_byte_enable : in STD_LOGIC_VECTOR(3 downto 0); -- byte masks for the write command cmd_data_in : in STD_LOGIC_VECTOR(31 downto 0); -- data for the write command data_out : out STD_LOGIC_VECTOR(31 downto 0); -- word read from SDRAM data_out_ready : out STD_LOGIC; -- is new data ready? -- SDRAM signals SDRAM_CLK : out STD_LOGIC; SDRAM_CKE : out STD_LOGIC; SDRAM_CS : out STD_LOGIC; SDRAM_RAS : out STD_LOGIC; SDRAM_CAS : out STD_LOGIC; SDRAM_WE : out STD_LOGIC; SDRAM_DQM : out STD_LOGIC_VECTOR( 1 downto 0); SDRAM_ADDR : out STD_LOGIC_VECTOR(12 downto 0); SDRAM_BA : out STD_LOGIC_VECTOR( 1 downto 0); SDRAM_DATA : inout STD_LOGIC_VECTOR(15 downto 0)); As you can see, the SDRAM works with words of 16 bits but the controller needs 32 bits. I tryied to understand how it works but I wasn't able. Can u explain a little bit how simple operation like single read/write can be performed throug the controller? Thanks Quote Link to comment Share on other sites More sharing options...
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