BASIC-MTHPAK

* NAME BASIC-MTHPAK DOC. 70181832000 REV. A PAGE 27

0896 * 0897 * 0898 * FLOATING POINT MULTIPLICATION 0899 * 0900 * CALLING SEQUENCE: 0901 * 0902 * JST M$22 MULFIPLICAND IN A AND B REGISTERS 0903 * DAC ARG2 POINTER TO MULTIPLIER 0904 * ......RETURN PRUDUCT IN A AND B REGISTER 0905 * 0906 * 0907 * THE ARGUMENTS ARE UNPACKED, THEIR SIGNS ARE SET POSITIVE, AND 0908 * THE SIGN OF THE PRODUCT IS SAVED. THEIR EXPONENTS ARE ADDED, THE 0909 * BIAS IS ADJUSTED, AND THE RESULT IS SAVED AS THE EXPONENT OF THE 0910 * PRODUCT. THE HIGH MULILPLICAND MANTISSA AND THE LOW MULTIPLIER 0911 * MANTISSA ARE MULTIPLIED, AS ARE THE HIGH MULTIPLLER MANTISSA AND 0912 * LOW MULTIPLICAND MANTISSA. THE TWO HIGH CROSS PRODUCT ARE SAVED. 0913 * THE HIGH MULTIPLICAND MANTISSA AND THE HIGH MULTIPLIER MANTISSA ARE 0914 * MULTIPLIED, AND THE HIGH CROSS PRODUCTS ARE ADDED TO THE LOW PRO- 0915 * DUCT. IF THERR IS OVERFLOW, THE HIGH PRODUCT IS INCREMENTED. 0916 * THE PRODUCT IS PACKED INTO FLOATING POINT FORMAT, AND THE SIGN IS 0917 * ADJUSTED. 0918 * 0919 * 0920 00530 0 000000 M$22 DAC ** MULTIPLICATION ENTRY 0921 00531 0 10 00455 JST MDAH JUMP TO ARGUMENT HANDLING ROUTINE 0922 * 0923 * PRODUCT EXPONENT DETERMINATION 0924 * 0925 00532 0 13 00201 IMA LOW SAVE HIGH MULTIPLIER MANTISSA, RECOVER 0926 * EXPONENT OF MULTIPLICAND 0927 00533 0 06 00152 ADD EXPT ADD EXPONENT OF MULTIPLIER 0928 00534 0 07 00572 SUB C200 SUBTRACT BIAS 0929 00535 0 04 00152 STA EXPT SAVE RESULTANT EXPONENT 0930 * 0931 * PRODUCT MANTISSA DETERMINATION 0932 * 0933 00536 000201 IAB LOAD LOW MULTIPLIER MANTISSA 0934 00537 0 10 00507 JST M$11 MULTIPLY BY HIGH MULTIPLICAND MANTISSA 0935 00540 0 000452 DAC RSLT X 0936 00541 000201 IAB LOAD HIGH CROSS PRODUCT 0937 00542 0 13 00453 IMA RSLT+1 AND SAVE, RECOVER LOW MULTIPLICAND MANTISSA 0938 00543 0 10 00507 JST M$11 MULTIPLY BY HIGH MULTIPLIER MANTISSA 0939 00544 0 000201 DAC LOW X 0940 00545 000201 IAB LOAD HIGH CROSS PRODUCT 0941 00546 0 13 00201 IMA LOW AND SAVE, RECOVER HIGH MULTIPLIER MANTISSA 0942 00547 0 10 00507 JST M$11 MULIIPLY BY HIGH MULTIPLICAND MANTISSA 0943 00550 0 000452 DAC RSLT X 0944 00551 000201 IAB SAVE HIGH PRODUCT MANTISSA 0945 00552 0 04 00452 STA RSLT X