Complex Commands

At times it will be necessary to specify the value of several fields in order to accomplish a single action. An example is an arithmetic operation in a microprogrammed computer, which usually requires the specification of operand sources, alu control signals, and result destination. The "command" statement can be used to group a set of commands together into a single complex command. The following is an example.

add_ab: command alu_add->alu,enab_a,enab_b,load_c

word add_ab

Once the command "add_ab" is defined, it can be used by many different "word" statements. Complex commands and simple commands may be mixed both on "word" statements and "command" statements. The order of the "command" statements and word statements does not matter, but "command" statements may not reference one another circularly.