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* NAME BASIC-MTHPAK DOC. 70181832000 REV. A PAGE 14

0432 * 0433 * 0434 * NORMALIZE AND REPACK INTO FLOATING POINT FORMAT 0435 * 0436 * CALLING SEQUENCE: 0437 * 0438 * JST NORM MANTISSA IN A AND B REGISTERS, EXPONENT IN 0439 * SPECIFIED TEMPORARY STORAGE LOCATION 0440 * ......RETURN FLOATING POINT IN A AND B REGISTERS 0441 * 0442 * 0443 * THE MANTISSA IS EXPECTED IN DOUBLE WORD FIXED POINT FORMAT 0444 * WITH THE BINARY POINT BETWEEN FIRST TWO BITS OF THE A REGISTER. 0445 * THE EXPONENT IS ASSUMED TO BE BIASED AND UNCOMPLIMENTED. IF THE 0446 * MANTISSA IS ZERO, THE ROUTINE EXITS WITH ZERO. OTHERWISE THE MAN- 0447 * I1SSA IS NORMALIZED AND ROUNDED. THEN IT IS SHIFTED LEFT TO 0448 * MAKE ROOM FOR THE EXPONENT, AND BIT ONE OF THE SECOND WORD IS 0449 * FILLED. THE EXPONENT IS DECREMENTED BY THE SHIFT COUNT OF THE 0450 * NORMALIZE, AND THEN TESTED FOR OVERFLOW AND UNDERFLOW. UNDERFLOW 0451 * AND OVERFLOW ARE FLAGGED BY NU AND NO RESPECTIVELY. OTHERWISE THE 0452 * TOTAL WORD IS FORMED, AND THE ROUTINE EXITS. 0453 * 0454 * 0455 00202 0 000000 NORM DAC ** ENTRY 0456 * 0457 * TEST FOR ZERO MANTISSA 0458 * 0459 00203 100040 SZE TEST HIGH MANTISSA EQUAL TO ZERO 0460 00204 0 01 00211 JMP N2 NO-JUMP TO NORMALIZE 0461 00205 000201 IAB YES-LOAD LOW MANTISSA 0462 00206 101040 SNZ TEST EQUAL TO ZERO 0463 00207 -0 01 00202 JMP* NORM YES-RETURN WITH ZERO 0464 00210 000201 IAB NO-REPOSITION 0465 * 0466 * NORMALIZE THE MANTISSA 0467 * 0468 00211 0 04 00272 N2 STA CNTR INITIALIZE THE SHIFT COUNTER TO ZERO 0469 00212 140040 CRA X 0470 00213 0 13 00272 IMA CNTR X 0471 00214 100000 SKP DON'T INCREMENT SHIFT COUNTER THE FIRST 0472 * TIME THROUGH 0473 00215 0 12 00272 IRS CNTR INCREMENT THE SHIFT COUNTER BY ONE 0474 00216 0411 77 LLS 1 SHIFT LEFT TO NORMALIZE 0475 00217 101001 SSC TEST FOR NORMAL RESULT 0476 00220 0 01 00215 JMP *-3 NO-LOOP TO INCREMENT THE SHIFT COUNTER 0477 00221 0401 77 LRS 1 RESTORE WITH WRONG SIGN 0478 00222 140024 CHS RESTORE THE SIGN 0479 * 0480 * ADD A ROUNDING FACTOR TO THE RIGHT OF THE LEAST SIGNIFICANT BIT 0481 * OF THE MANTISSA
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