Question

SystemVerilog adds system tasks and system functions as described in the following sections. In addition, SystemVerilog extends the behavior of the following:

• %u and %z format specifiers:
  • For packed data, %u and %z are defined to operate as though the operation were applied to the equivalent vector.
  • For unpacked struct data, %u and %z are defined to apply as though the operation were performed on each member in declaration order.
  • For unpacked union data, %u and %z are defined to apply as though the operation were performed on the first member in declaration order.
  • %u and %z are not defined on unpacked arrays.
  • The count of data items read by a %u or %z for an aggregate type is always either 1 or 0; the individual members are not counted separately.
• $fread

$fread has two variants—a register variant and a set of three memory variants.

The register variant,

$fread(myreg, fd);

• is defined to be the one applied for all packed data.
• For unpacked struct data, $fread is defined to apply as though the operation were performed on each member in declaration order.
• For unpacked union data, $fread is defined to apply as though the operation were performed on the first member in declaration order.
• For unpacked arrays, the original definition applies except that unpacked struct or union elements are read as described above.