Useful OVM-e Snippets Print
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Thursday, 24 December 2009 16:41

How to activate Specman Profiler? How to get rid of automatic vr_ad coverage? Let's find out.


How to activate Specman Profiler?

extend sys {
setup() is also {
specman("set profile");



How to get rid of automatic vr_ad coverage?

extend sys {
setup() is also {
set_cover("vr_ad_reg", FALSE);



How to continue simulation regardless of DUT errors?

extend sys {
setup() is also {
set_check( "...", ERROR_CONTINUE );
// set_check( "...", IGNORE );  -- use this to disable DUT errors completely



How to instantiate a logger?

extend your_unit {
logger: message_logger is instance;
keep soft logger.verbosity == MEDIUM;
keep soft logger.tags == {NORMAL};
short_name(): string is {
result = append("YOUR_UNIT_NAME"); // can also be a dedicated evc_name
// Constrain the output coloring for better visibility
short_name_style(): vt_style is {
result = BLUE;



How to generate a random list of numbers?

gen_random_list_of_numbers(num_of_items: uint, max_val: uint): list of uint is {
assert num_of_items <= max_val + 1;
var next_item: uint;
for i from 1 to num_of_items {
gen next_item keeping {
it <= max_val;
it not in result;
result = result.sort(it);

How to implement register side affect with vr_ad?

extend MY_REG vr_ad_reg {
post_access(direction : vr_ad_rw_t) is {
if direction == WRITE then { // or READ
// get pointer to the enclosing reg file
var rgf := get_parents()[0].as_a(REG_FILE_TYPE vr_ad_reg_file);
// side affect
if bit0 == 1 then {
rgf.another_register.another_bit = 1;



How to control generation of Boolean variables elegantly?

gen_true_or_false(true_prob: uint): bool is {
assert that true_prob <= 100;
gen result keeping {
soft it == select {
true_prob      : TRUE;
(100-true_prob): FALSE;



How to declare a sequence?

sequence my_prefix_seq_s using
item = my_prefix_frame_s,
created_kind   = my_prefix_seq_kind_t,
created_driver = my_prefix_driver_u,
sequence_type  = my_prefix_any_sequence_s,  // optional
sequence_driver_type = my_prefix_any_sequence_driver_u; // optional



How to use method ports?

struct packet {
just_a_number: uint;
// define a method type
 method_type packet_method_t (p: packet);
// add an output port
unit tx_u {
broadcast_packet: out method_port of packet_method_t is instance;
send_packet_to_port() is {
// add an input port
unit rx_u {
receive_packet: in method_port of packet_method_t is instance;

 receive_packet(p :packet)  is {
message(LOW,"packet received");
print p using hex;
//make a one-to-many connection
extend sys {
tx: tx_u is instance;
rx_list[2] : list of rx_u is instance;

 connect_ports() is also {
for each in rx_list {
do_bind(tx.broadcast_packet, it.receive_packet);


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