the stack frame Bit and field operators Bit set (bit number given by syllable following instruction) Dynamic bit set (bit number given by contents of B) Bit reset (bit number given by syllable following instruction) Dynamic bit reset (bit number given by contents of B) Field isolate (field given in syllables following instruction) Dynamic field isolate (field given in top of stack words) Field transfer (field given in syllables following instruction) Dynamic field transfer (field given in top of stack words) Field insert (field given in syllables following instruction) Dynamic field insert (field given in top of stack words) Count binary ones in the top of stack word (A or AX) Scale left Dynamic scale left Scale right Dynamic scale right Scale right save Dynamic scale right save Scale right final Dynamic scale right final Scale right round Dynamic scale right round Literal operators Load following code word onto top of stack Set top of stack to following 16 bits in code stream Set top of stack to following code syllable Shortcut for LT48 0 Shortcut for LT48 1 Descriptor operators Index create a pointer (copy descriptor) from a base (MOM) descriptor Index and load name (resulting in an indexed descriptor) Index and load value (resulting in a data value) Evaluate descriptor (follow address chain until data word or another descriptor found) Stack operators Push down stack register Pop top of stack Exchange top two words of stack Rotate stack up (top three words) Rotate stack down (top three words) Duplicate top of stack Mark stack (build a new stack frame resulting in an MSCW on the top, — followed by NAMC to load the PCW, then parameter pushes as needed, then ENTR) Insert an MSCW in the B register. Fetch a value onto the stack as described above Place an address couple (IRW stack address) onto the stack as described above Convert an IRW as placed by NAMC into an SIRW which references data in another stack. Move to stack (process switch only done in one place in the MCP) Store operators Store destructive (if the target word has an odd tag throw a memory protect interrupt, — store the value in the B register at the memory addressed by the A register. — Delete the value off the stack. Store non-destructive (Same as STOD but value is not deleted – handy for F := G := H :=