ROM Output

Recall that the rom preprocessor prepares data for the FHDL compiler. Since the FHDL compiler cannot handle buses whose width is greater than 32, the output of the rom will be grouped into blocks of 32 bits starting from the left. Of course, the last (or only) block may have fewer than 32 bits. Depending on how the output of the ROM is used by the rest of the circuit, it may be convienient to group the outputs differently. The "output" statement can be used to do this. The operands of the output statement determine how the outputs of the ROM are grouped. One group of outputs will be created for each operand. Each operand must be an expression that gives the size of the group. The value of the expression must range from 1 to 32. An example of an output statement is given below.

output awid,bwid,cwid

The most convenient grouping of outputs is by field. Note that this grouping is logical rather than physical.