Forum Discussion
Altera_Forum
Honored Contributor
Honored ContributorAvalon_ mm_ master wrapper (vhdl)
Hello,
I have written a code for CDMA Encoding and CDMA Decoding using VHDL Language. Now i have to create as a custom IP using component editor.Here i want a help regarding the avalon signals. In my system , the output from NIOS-II processor will be given to CDMA_Encoding(it encodes 32-bit data from NIOS-II and convert it to 16-bit data) and then given to avalon interface. Similarly from avalon interface i will get 16-bit data,which is given to CDMA decoding( it again converts 16-bit data into 32-bit,as original output from NIOS-II) and then given to slave(like SDRAM or Flash Memory). NIOS-->CDMA_ENCODING-->AVALON-->CDMA_DECODING-->SLAVE. this is the flow of system. Kindly help me regarding creating custom IP to sync with avalon. i am not able to understand , which signals to be used after reading avalon specification manual. entity of my custom logic is given below. CDMA_ENCODING:entity CDMA_ENCODING is
port (rst_n : in std_logic;
clk : in std_logic;
PI: IN STD_LOGIC_VECTOR(0 TO 31);
output :buffer std_logic_vector (0 to 15));
end CDMA_ENCODING; entity CDMA_DECODING is
port (
rst_n : in std_logic;
clk : in std_logic;
PI: IN STD_LOGIC_VECTOR(0 TO 15);
output :buffer std_logic_vector (0 to 31));
end CDMA_DECODING;22 Replies
Altera_Forumfor reading....
for writing..... PI_WRAP_EN,PI_WRAP_DE are cdma encoding and decoding port maps. here i didnot add byte enable .if avs_m0_read='1' then avm_m1_read<=avs_m0_read; avm_m1_address<=avs_m0_address; --avm_m0_waitrequest<='1'; avs_m0_waitrequest<='1'; end if;
is that read and write operations are correct. Tell me sir, Read and write should be '0' or '1' to start operation. thank you very much in advance.if avs_m0_write='1' then avm_m1_write<=avs_m0_write; avm_m1_address<=avs_m0_address; avs_m0_waitrequest<=avm_m1_waitrequest; avs_m0_waitrequest<='1'; PI_WRAP_DE<=avs_m0_writedata; avm_m1_writedata<=OUTPUT_WRAP_DE; end if;- Altera_Forum--- Quote Start --- for reading....
for writing..... PI_WRAP_EN,PI_WRAP_DE are cdma encoding and decoding port maps. here i didnot add byte enable .if avs_m0_read='1' then avm_m1_read<=avs_m0_read; avm_m1_address<=avs_m0_address; --avm_m0_waitrequest<='1'; avs_m0_waitrequest<='1'; end if;
is that read and write operations are correct. Tell me sir, Read and write should be '0' or '1' to start operation. thank you very much in advance. --- Quote End --- You need to start simulating your design by using a simulator. Some quick comments: - The "if avs_m0_read='1' then" (and the same for the write) are not needed. Just look at the code you wrote after the if/then "avm_m1_read<=avs_m0_read" but in order to execute the statement avs_m0_read must already be one which means that "avm_m1_read" will end up being '1' forever once 'avs_m0_read' first gets set to 1. - Ask yourself what do you think happens when you hit the statement "avs_m0_waitrequest<='1';". No where will it ever get set back to '0', which means the interface will forever be saying to wait which means it will hang. The entire 'if/then' statement needs to be removed. Like I said, it's time that you start to run the simulator with your code. Verify that your implementation of the various Avalon signals matches what the specification says. Kevin Jenningsif avs_m0_write='1' then avm_m1_write<=avs_m0_write; avm_m1_address<=avs_m0_address; avs_m0_waitrequest<=avm_m1_waitrequest; avs_m0_waitrequest<='1'; PI_WRAP_DE<=avs_m0_writedata; avm_m1_writedata<=OUTPUT_WRAP_DE; end if;
