Code Field
This field contains a code which identifies the machine operation (add, subtract, jump, etc.) to be performed: hence the term operation code or op-code. The instructions described in Sections 3. 3 thru 3.11, are each identified by a mnemonic label which must appear in the code field. For example, since the “jump unconditionally” instruction is identified by the letters “JUN”, these letters must appear in the code field to identify the instruction as “jump unconditionally”.
There must be at least one space following the code field. Thus:
LAB, JUN AWY
is legal, but
LAB, JUNAWY
is illegal.