**208 Part 3 The instruction-set processor level: variations in the processor **

Section 1 Processors with greater than 1 address per instruction

*c *If j = 0, do not change u and v.

If j = 1, add one to v after each execution.

If j = 2, add one to u after each execution.

If j = 3, add one to u and v after each execution.

The modification of the u address and v address is done in program control registers. The original form of the instruction in storage is unaltered.

*d *On completing n executions, take (F_{1}), as the next instruction. F_{1 }normally contains a manually selective jump whereby the computer is sent to w for the next instruction after the repeat.

*e *If the repeated instruction is a jump instruction, the occurrence of a jump terminates the repetition. If the instruction is a Threshold Jump or an Equality Jump, and the jump to address v occurs, (Q) is replaced by the quantity j, (n - r), where r is the number of executions that have taken place.

Floating point instructions

**64 Add FAuv:** Form in Q the normalized rounded packed floating point sum (u) + (v).

**65 Subtract FSuv:** Form in Q the normalized rounded packed floating point difference (u) - (v).

**66 Multiply** **FMuv: **Form in Q the normalized rounded packed floating point product (u) . (v).

**67 Divide FDuv:** Form in Q the normalized rounded packed floating point quotient (u) ¸
(v).

**01 Polynomial Multiply FPuv:** Floating add (v) to the floating product (Q)_{i }. (u), leaving the packed normalized rounded result in Q.

**02 Inner Product FIuv: **Floating add to (Q)_{i} the floating product (u) . (v) and store the rounded normalized packed result in Q. This instruction uses MC location F_{4 }= 00003 for temporary storage, where (F_{4})_{f} = (Q)_{i}. The subscripts and f represent "initial" and "final."

**03 Unpack UPuv:** Unpack (u), replacing (u) with (u)_{M} and replacing (v)_{c} with (u)_{c }or its complement if (u) is negative. The characteristic portion of (u)_{f} contains sign bits. The sign portion and mantissa portion of (v)_{f}* *are set to zero. *Note. *The subscripts M and C denote the mantissa and characteristic portions.

**04 Normalize Pack NPuv:** Replace (u) with the normalized rounded packed floating point number obtained from the possibly unnormalized mantissa in (u)_{i} and the biased characteristic in (v)_{c}. *Note. *It is assumed that (u)_{i} has the binary point between u_{27 }and u_{26 }that is, that (u)_{i} is scaled by 2^{-27}.

**05 Normalize Exit NEj-: **If j = 1 normalize without rounding until a master clear or until the instruction is again executed with j = 0.

References

Univac Scientific Electronic Computing System Model 1103A, Form EL 338