
VHDL Tutorials
Verifying a Slave DUT
Mentor VIP AE AXI3/4 User Guide, V10.2b
619
September 2013
The burst length argument passed to the create_read_transaction() procedure is 1 less
than the number of transfers (beats) in the burst. This aligns the burst length argument
value with the value placed on the ARLEN protocol signals.
The read transaction is then executed onto the protocol signals by calling the
execute_transaction() procedure. The read data is obtained by calling the get_data_words()
procedure twice to get the data_words transaction field values. The result of the read data is
compared with the expected data—and a message displays the transcript.
Example 11-13. Read Burst Transaction Creation and Execution
create_read_transaction(16, 1, tr_id, index, axi4_tr_if_0(index));
execute_transaction(tr_id, index, axi4_tr_if_0(index));
get_data_words(data_words, 0, tr_id, index, axi4_tr_if_0(index));
if(data_words(31 downto 0) = x"ACE0ACE1") then
report "master_test_program: Read correct data (hACE0ACE1) at
address (16)";
else
hwrite(lp, data_words(31 downto 0));
report "master_test_program: Error: Expected data (hACE0ACE1) at
address (16), but got " & lp.all;
end if;
get_data_words(data_words, 1, tr_id, index, axi4_tr_if_0(index));
if(data_words(31 downto 0) = x"ACE2ACE3") then
report "master_test_program: Read correct data (hACE2ACE3) at
address (20)";
else
hwrite(lp, data_words(31 downto 0));
report "master_test_program: Error: Expected data (hACE2ACE3) at
address (20), but got " & lp.all;
end if;
In the complete Master Test Program, a subsequent read transaction is created and executed in a
similar manner to that shown in Example 11-13. See VHDL AXI4 Master BFM Test Program
listing for details.
Outstanding Write Burst Transaction Creation and Execution
The code excerpt in Example 11-14 uses the AXI4 Master BFM create_write_transaction()
procedure to create a write burst transaction by providing the start address and burst length
arguments. The actual length of the burst on the protocol wires is 3+1=4.
The burst length argument passed to the create_read_transaction() procedure is 1 less
than the number of transfers (beats) in the burst. This aligns the burst length argument
value with the value placed on the ARLEN protocol signals.
Komentarze do niniejszej Instrukcji