XDS 910, Reference Manual

Page 1: ...Xerox Data Systems Reference Manual...

Page 2: ...Multiply Step CONTROL DIS A T 65 Divide Step 10 HLT 00 Halt 15 NOP 20 No Operation 16 LOGICAL EXU A T 23 Execute Instruction in Memory 16 ETR A T 14 Extract 10 BREA KPOINT TESTS MRG A T 16 Merge 10 E...

Page 3: ...XOS 910 COMPUTER REFERENCE MANUAL 90 00 080 February 1970 Price 3 25 Xerox Data Systems 70i South Aviation Bouievard Ei Segundo Caiifornia 90245 91963 1970 Xerox Data Systems Inc Printed in U S A...

Page 4: ...Reference Manual XDS 910 925 Programmed Operators Technical Manual XDS 910 920 Computer EXAMINER Diagnostic System Technical Manual XDS FORTRAN II Reference Manual XDS 900 Series FORTRAN II Operation...

Page 5: ...ns 18 Interrupt Arm Enable Response 19 Interrupt Enable Disable Instructions and Tests 20 ILLUSTRATIONS Special Systems Interrupts 21 4 INPUT OUTPUT SYSTEM XDS910 Computer Frontispiece iv l XDS 910 Co...

Page 6: ...XDS 910 Computer iv...

Page 7: ...rammable registers Buffered input output at rates in excess of 60 000 characters second simultaneous with computation Standard input output Display and manual control of internal registers Full word i...

Page 8: ...ons with the 14 least significant bits address portion of the X register provide an indexing capability of up to 16 384 words The 14 bit P register Program Counter contains the memory address of an in...

Page 9: ...g Before accessing a memory word the computer checks the power to ensure that the entire read write cycle can be successfu Ily compl eted If it detects a power loss the computer halts Special logic op...

Page 10: ...ually used to de note Programmed Operators The high order 1 bit in combination with tags of 0 2 4 6 results in tags of 1 3 5 and 7 respectively Programmed Operators are discussed further in this secti...

Page 11: ...ation and program running time ADDRESS MODIFICATION Address modification is accomplished through indexing and indirect addressing used singly or in combination In both indexing and indirect addressing...

Page 12: ...s from program to program or from section to section of the same program The total number of Programmed Opera tors is without limit but it is inconvenient to use more than 64 in one program Other comp...

Page 13: ...ocation of the BRM instruction A RETURN BRANCH BRR instruction accompl ishes the return to the main program the BRR adds one to the stored P reg ister value and transfers control to that location See...

Page 14: ...t Thus 0200 200 8 and 200 200 10 The term effective memory location refers to the lo cation in memory from which the operand is taken at the conclusion of all indirect addressing and indexing This ter...

Page 15: ...of the same sign but the sign of the result in the A register is opposite over flow has occurred and the computer has set the OVER FLOW indicator Affected A Of Timing 2 MIN o 1 2 3 61 I MEMORY INCREME...

Page 16: ...register left one bit position and copies the complement of AO into B23 If AO MO the contents of the memory location determ ined by the effective address are sub tracted from the A register If AO I MO...

Page 17: ...epending on the va lues of bit positions 10 and 11 of the instruction word 10 11 Function o 0 Exchange A and B XAB o 1 Copy B into A clear B BAC 1 0 Copy A into B c lear A ABC 1 1 C lear A and B CLR I...

Page 18: ...branch 2 if no branch Example Location Contents Instruction X register 00777 2 35 01500 STA 01500 2 77777776 01000 041 01006 BRX 01006 77777777 01001 2 76 02000 LDA 02000 2 77777777 01006 041 01001 BR...

Page 19: ...the computer skips the next instruction in sequence after SKM and executes the following instruction If the specified bits are not identical the computer executes the next instruction in sequence afte...

Page 20: ...on affects only bits 18 23 of the address field It is thus possible to index the number of shifts without affecting bits 10 and 14 11 which control the method of shifting During in direct addressing t...

Page 21: ...th register as if it were circular and cycles it onto itself It loses no bits Affected AB Timing 2 N Example LCY 9 067 20011 Before After Execution Execution A 76543210 43210012 B 01234567 34567765 NO...

Page 22: ...tion plus one following the EXU If the contents of the effective memory location are another EXU the above process repeats wi th the norma I return be ing the initial EXU location plus one This proces...

Page 23: ...re Approxi mate Mne Execution monic Name Function Time FLA Floating Floating A B 896 sec Add M 1 M A B FLS Floating Floating A B 1016 sec Subtract M 1 M A B FLM Floating Floating A B 1696 sec Multiply...

Page 24: ...et to produce a steady signal the waiting state begins If no higher priority level is in the active state the signal from the Waiting ff sets the in terrupt ff At the end of the execution cycle of the...

Page 25: ...rrupted program and no record is kept of the contents of the program counter wh en the branch is executed NON INTERRUPTABLE INSTRUCTIONS If an INCREMENT INDEX AND BRANCH BRX instruc tion is being exec...

Page 26: ...g 1 OIR DISABLE INTERRUPTS EOM 020004 002 20004 DIR unconditionally resets the Enable ff Also if the INTERRUPT ENABLE switch is in the COMPUTER position 20 the INTERRUPT ENABLED indicator is turned of...

Page 27: ...r disarmed in groups of sixteen i e interrupt levels 0200 0217 0220 0237 etc and only by a specific combination of the two instructions ARM INTERRUPTS AIR and PARALLEL OUTPUT POT and a control word Th...

Page 28: ...em turns INTERRUPT ENABLED indicator on Prepare the Arm Interrupt Control Unit to receive a control word Transmit the control word in location CW1 to the Arm Interrupt Control Unit An AIR must precede...

Page 29: ...cifies the number of characters to be contained in each word during the transmission Each buffer may have an interlace associated with it Interlace allows input output of blocks of data words with buf...

Page 30: ...omatically places the word when assembled into memory 24 During output words come from memory into the WAR where the buffer disassembles them into the SeR one 6 bit character at a time Depending on th...

Page 31: ...OM initiates Output II 1st I 2nd I 3rd I 4th I I I I 23 23 I 23 I 23 I I 0 0 0 0 5 6 1112 1718 1st 3rd 6 7 1314 1st I 2nd I 7 8 1 I 1516 1st 2nd 8 9 1st 2nd 9 10 2nd 1st I 1011 1st I 11 12 2nd I 23 20...

Page 32: ...instruction configura tions has a mnemonic recognized by META SYMBOL see Standard Buffer SKS Instructions page 29 The setting of two bits 10 11 within the instruction format determines the different m...

Page 33: ...05 Paper Tape Input No 2 45 Paper Tape Punch Output No 2 06 Card Reader Input No 1 46 Card Punch Output No 1 07 Card Reader Input No 2 47 Card Punch Output No 2 10 Magnetic Tape Input No 0 50 Magneti...

Page 34: ...bit in bit position 12 terminates outputs or converts magnetic tape inputs to scanll 28 STAN DARD BUFFER EOM INSTRUCTIONS Severa I EOM function configurations have standard uses These have standard a...

Page 35: ...ion Bit Designation xxxx Octal Octal Position Value 4 7 Function Bit positions 12 through 23 specify the test Each of these tests cause the computer to skip when the test condition is true Selecting m...

Page 36: ...ctly in the specified memory location without disturbing any internal registers I O Device 30 Central Processor Memory MEMORY INTO W MIW causes a word to be taken from a specified memory location and...

Page 37: ...rity bit is set and the con trol panel ERROR indicator is lighted Note that such an error does not stop the computer Facilities are provided in the computer that allow the program to interrogate and r...

Page 38: ...an End of Word interrupt is generated while the tape is still moving If a read or scan command is sent to the tape within 500 microseconds the reading or scanning continues If no command is given in...

Page 39: ...put of up to 1023 01777 words The starting address of the input output operation is right justified in bit po sitions 10 23 of the data word and is transmitted to bit positions 12 25 of the interlace...

Page 40: ...End of Transmission inter rupt signal is generated and the End of Word interrupt returns to normal single word operations DIRECT PARALLEL INPUT OUTPUT EOM and SKS instructions control parallel input o...

Page 41: ...it input output trans missions Execution of an EOM system mode causes an 8 microsecond signal to be transmitted to one of a possi ble 32 768 signal destinations EOM ENERGIZE OUTPUT M 02 89 101112 Bit...

Page 42: ...STER DISPLAY Moving the switch to STEP causes the computer to execute the current contents of the C register load the C register with the next instruction in sequence and automatically return to an id...

Page 43: ...ay consists of 24 binary indicators that show the contents of the register selected by the REGISTER switch With the RUN IDLE STEP switch in IDLE pressing the CLEAR pushbutton clears the selected regis...

Page 44: ...If type writer output is accomplished using inteilace the intei lace control automatically terminates output clears the unit address register in the buffer If single word trans mission is used for ty...

Page 45: ...f location WAIT 00043073 which furnishes a 1 bit in bit position 9 and a count 2500 in two s complement form in bit positions 10 23 No operation This instruction causes the instructions NOP and BRX to...

Page 46: ...r rate error occurs during a paper tape read operation the buffer error flip flop is set and the ERROR indicator on the computer control panel is turned on 40 Example Read a block of binary tape of an...

Page 47: ...el 033 from the active state means indirect address bit set PAPER TAPE PUNCH The paper tape punch is used primari Iy for punching pro grams and or data to be loaded back into memory later The punch is...

Page 48: ...aper Tape This routine punches a block of eight words from locations 02000 through 02007 A l inch gap precedes and follows the block The routine is a closed subroutine that does not use interrupts the...

Page 49: ...ingle card may represent up to 160 characters 40 words at 4 characters word in binary format Card A Con v l L u _ w c D _e c t JJ T C u J o t J o 0 c J o 0 c c c c u c c t lc 9 c t J o c t C c t c 2 c...

Page 50: ...The reader reads characters into the buffer When the buffer is full an End of Word interrupt is initiated at location 031 031 RETRN BRM PZE WIM MIN BRU RETRN READ READ RETRN Reserve the return entry l...

Page 51: ...s ready when CRT is executed the computer skips the next instruction insequence and executes the following instruction If the card reader is not ready the computer executes the next instruction in seq...

Page 52: ...is switch removes power from the card reader and turns off all indicators except the EOF ON and END OF FILE 46 CARD PUNCH Before starting a card punch operation the punch should be loaded and tested a...

Page 53: ...not become ready can also be placed here This instruction is executed if the punch is ready It alerts the W buff er with interlace connects card punch 1 to the W buffer and starts a card moving toward...

Page 54: ...f 132 print hammers The drum rotates 56 c harac ters in Iines of 132 each pas the hammer bank Upon command from the computer the print hammers selected by the buffer drive the paper against the ribbon...

Page 55: ...ht channel paper tape Putting a punch in the specified channel at the desired vertical spacing selects the channel upspace Channel 1 is the top of form channel channel 7 is the bottom of form channel...

Page 56: ...followi ng instruction 50 TERMINATING LINE PRINTER OUTPUT When the single word mode of transmission is used for printing on the Iine printer each character transm ission for a Iine must be followed by...

Page 57: ...ogram prints two lines at the top of a page with a single upsapace between Assume that the printer is ready or is becoming ready after a print operation The program is a closed subroutine for printer...

Page 58: ...information the seventh is a par ity check Both even and odd pari ty are used Tape can be recorded in binary mode using odd parity In this mode the six bit characters from the tape are recorded witho...

Page 59: ...buffer This instruction should be used before any write operation to determine whether it is possible to perform the oper ation BTT 0 BEGINNING OF TAPE TEST Skip if not Beginning of Tape SKS 0 1201n 0...

Page 60: ...follow the new record can be read This means that a record in the midd Ie of a fi Ie cannot be updated or rewritten it it is desired to read the records that follow it Any 54 errors detected either b...

Page 61: ...nches around the not ready exit This instruction branches to an assumed routine that determines what is not ready This instruction addresses the W buffer connects magnetic tape unit 1 to it specifies...

Page 62: ...lace The 4 characters word and BCD modes are specified The octal configuration is 0 02 02611 Transmit the word count and starting address to the buffer Branch back to the main program and clear the in...

Page 63: ...peration when the tape is read In addition to writing under program control magnetic tape can also be erased under program control Tape may be erased by addressing it with an erase unit ad dress When...

Page 64: ...the following one is executed The octal configuration of the instruction is o40 14011 Branch and mark to an assumed routine that calls the operator and in structs him to insert file protect ring on ma...

Page 65: ...50 51 52 53 54 55 56 57 Backspace C0 1 32 12 2 12 3 12 4 12 5 12 6 12 7 12 8 12 9 12 00 12 8 3 12 8 4 12 8 5 12 8 6 12 8 7 60 61 62 63 64 65 66 67 70 71 72 73 74 75 76 77 Tab CD 0 62 63 64 65 66 67 70...

Page 66: ...119 209 289 550 781 25 0 000 000 059 604 644 775 390 625 O 000 000 029 802 322 387 695 312 5 O 000 000 014 901 161 193 847 656 25 0 000 000 007 450 580 596 923 828 125 0 000 000 003 725 290 298 461 91...

Page 67: ...48 0249 0250 0251 0252 0253 0254 0255 0750 0488 0489 0490 0491 0492 0493 0494 0495 1 0760 0496 0497 0498 0499 0500 0501 0502 0503 0770 0504 0505 0506 0507 0508 0509 0510 0511 I 0 2 3 6 I 0 t 2 3 4 6 7...

Page 68: ...658 1659 1660 1661 1662 1663 3570 1912 1913 3200 1664 1665 1666 1667 1668 1669 1670 1671 3600 1920 1921 3210 1672 1673 1674 1675 1676 1677 1678 1679 3610 1928 1929 3220 1680 1681 1682 1683 1684 1685 1...

Page 69: ...48 2749 2750 2751 2755 2756 2757 2758 2759 2763 2764 2765 2766 2767 2771 2772 2773 2774 2775 2779 2780 2781 2782 2783 2787 2788 2789 2790 2791 2795 2796 2797 2798 2799 2803 2804 2805 2806 2807 1 2811...

Page 70: ...50 3944 3945 7560 3952 3953 7570 3960 3961 7200 3712 3713 3714 3715 3716 3717 3718 3719 7600 3968 3969 7210 3720 3721 3722 3723 3724 3725 3726 3727 7610 3976 3977 7220 3728 Jq29 3730 3731 3732 3733 37...

Page 71: ...29687 035 056640 135 181640 235 306640 335 431640 036 058593 136 183593 236 308593 336 433593 037 060546 137 185546 237 310546 337 435546 040 062500 140 187500 240 312500 340 437500 041 064453 141 189...

Page 72: ...8 000335 000843 000036 000114 000136 000358 000236 000602 000336 000846 000037 000118 000137 000362 000237 000606 000337 000850 000040 000122 000140 000366 000240 000610 000340 000854 000041 000125 00...

Page 73: ...5 001575 000735 001819 000436 001091 000536 001335 000636 001579 000736 001823 000437 001094 000537 001338 000637 001583 000737 001827 000440 001098 000540 001342 000640 001586 000740 001831 000441 00...

Page 74: ...imal equivalent of a binary two s complement number a Express as an octal number b Subtract one and form the complement c Find the decimal equivalent The negative of the result is thedecimal equivalen...

Page 75: ...stepping instructions INSPECT MEMORY CONTENTS 1 Set the RUN IDLE STEP switch to IDLE 2 Set the REGISTER switch to C 3 Press CLEAR and enter a BRU to the memory loca tion to be examined into REGISTER...

Page 76: ...SKS 66 or 67 20 NaP 00 HLT Shift Class other ADDRESS EXU I S C other HLT Execute instruction no a X If X9 I S P If X 0 P 1_ P Figure 9 Instruction Execution Diagram Set hiehest priority interrupt leve...

Page 77: ...register ADDRESS Copy the address field of the C register into the 5 register EXECUTION IA If the instruction operand is indirectly addressed a 1 in bit 9 of the instruction word load the C registe w...

Page 78: ...Always armed Optional Arming Feature Arm with AIR and POT i 03 6 7 2 1 1 03673 I 1 I I 1 1 I 04001 AIR l 04002 POT 02051 r 0 45 0 0 D I_R__ i Figure 10 Priority Interrupt System Diagram...

Page 79: ...e instruction is not a BRX or EOM the S regi ster is set to 031 BRM 02000 in that location is brought out to the C reg ister and executed with the following results a The contents of the Program Count...

Page 80: ...PACK CC l CC Shift WAR left 6 I I O UAR Send EOTt4 i EOM C 18 23 UAR C15 16 CCR Clear SF Clear E Start device READY Suffer ready for new EOM FULL Set SF OUTPUT Figure 11 Buffer Operation Single Word T...

Page 81: ...of the SCR are copied into bits 18 23 of a 24 bit word assembly register WAR WORD If the number of characters word specified by the EOM have been assembled set BF and go to EOR2 PACK Decrease CC by 1...

Page 82: ...ed or disassembled as described in Single Word Transmission NEXT The contents of the MAR are incremented by 1 and the contents of the WCR are decremented by 1 EaT If an end of record signal has been r...

Page 83: ...ty to change the arithmetic modeofaprogram with out recoding the arithmetic portions of the program For example if the programmer codes all arithmetic instruc tions as programmed operators he could si...

Page 84: ...ate Fixed Point Double Precision Subtract Fixed Point Double Precision Square Root Fixed Point Mnemonic EXF EXP FFF FLA FLD FLM FLN FLS FSA FSD FSM FSN FSQ FSS LDE LDP LGF LOG LQP LRSH LTP MUL SIN SKB...

Page 85: ...INCREMENT M 1 M 3 9 MDE 60 MEMORY DECREMENT M 1 M 3 9 SUB 54 SUBTRACT M FROM A A M A 2 9 MUS 64 MULTIPLY STEP Add or subtract M from A based on B 21 23 1 4 AB AB DIS 65 DIVIDE STEP 2 AB AB AO B 23 If...

Page 86: ...right N places 2 N 14 RCY 066200XX RIG HT CYCLE AB AB cycled right N places 2 N 14 LSH 067000XX LEFT SHIFT AB AB shift left N places 2 N 15 LCY 067200XX LEFT CYCLE AB AB cycled left N places 2 N 15 N...

Page 87: ...TO STORE ADDRESS 29 IN W BUFFER ASC 1 o02 12100 ALERT TO STORE ADDRESS 29 IN Y BUFFER INPUT OUTPUT MIW 12 MINTO W BUFFER WHEN M W 2 wait 30 EMPTY MIY 10 MINTO Y BUFFER WHEN M Y 2 wait 30 EMPTY WIM 32...

Page 88: ...0 1 040 14046 CARD PUNCH READY TEST Skip if Card Punch Ready 1 2 48 PBT 0 1 040 12046 PUNCH BUFFER TEST Skip if Punch Buffer Ready 1 2 48 PCD 0 1 4 002 02646 PUNCH CARD DECIMAL 46 Hollerith PCB 0 1 4...

Page 89: ...SCAN 57 SFB 0 n 4 o02 0363n SCAN FORWARD IN BINARY 55 SFD 0 n 4 0020263n SCAN FORWARD IN 55 DECIMAL BCD SRB 0 n 4 o02 0763n SCAN REVERSE IN BINARY 55 SRD 0 n 4 0020663n SCAN REVERSE IN DECIMAL 55 BCD...

Page 90: ...4 PRINT LINE PRINTER 49 o02 03606 RCB 0 1 4 READ CARD BINARY 45 o02 0361n RTB 0 n 4 READ TAPE IN BINARY 54 o02 0363n SFBO n 4 SCAN FORWARD IN BINARY 55 o02 03646 PCB 0 1 4 PUNCH CARD BINARY 45 o02 036...

Page 91: ...7 STX STORE INDEX 9 40 SKS SKIP IF SIGNAL NOT SET 9 040 1021n MAGPAK TEST 54 040 1041 n TRT 0 n TAPE READY TEST 53 040 11006 CFT 0 1 CARD READER END OF FILE TEST 45 040 11 01 n ETT 0 n END OF TAPE TES...

Page 92: ...2 43 BRM MARK PLACE AND BRANCH 12 046 00000 XAB EXCHANGE A AND B 11 046 10000 BAC COpy B INTO A CLEAR B 11 046 20000 ABC COpy A INTO Bf CLEAR A 11 04630000 CLR CLEAR AB 11 51 BRR RETURN BRANCH 12 53 S...

Page 93: ...EST 16 BRM 43 MARK PLACE AND BRANCH 12 BRR 51 RETURN BRANCH 12 BRTW 04021000 W BUFFER READY TEST 29 BRTY 04022000 Y BUFFER READY TEST 29 BRU 01 BRANCH UNCONDITIONALLY 12 BRX 41 INCREMENT INDEX AND BRA...

Page 94: ...61 MEMORY INCREMENT 9 MIW 12 MINTO W BUFFER WHEN EMPTY 30 MIY 10 MINTO Y BUFFER WHEN EMPTY 30 MRG 16 MERGE 10 MUS 64 MULTIPLY STEP 9 NOD 067 100XX NORMALIZE AND DECREMENT X 15 NOP 20 NO OPERATION 16...

Page 95: ...F M AND A DO NOT COMPARE ONES 13 SKG 73 SKIP IF A GREATER THAN M 13 SKM 70 SKI P IF A M 0 N B MASK 13 SKN 53 SKIP IF M NEGATIVE 14 SKS 40 SKIP IF SIGNAL NOT SET 29 SRB 01 n 4 o02 0763n SCAN REVERSE IN...

Page 96: ...nterlaced Input Output 32 INDEX Line Printer 48 Load Store Instructions 8 Logica I Instructions 10 Magnetic Tape Format 52 Reading 54 Unit Controls 57 Unit Tests 53 Writing 57 Memory SDS 910 3 Word Fo...

Page 97: ...ice Building 190 Moore Street Hackensack N J 07601 201 489 0100 The Fortune Building 280 North Central Avenue Hartsdale New York 10530 91 4 948 2929 1301 Avenue of the Americas New York City N Y 10019...

Page 98: ...DT5 0 n o40 1661 n Density Test 556 BPI 53 CRT 0 1 040 12006 Cord Reader Ready Test 45 DT8 0 n 040 1721n Density Test 800 BPI 53 FCT 0 1 040 14006 First Column Test 45 TFT 0 o40 13610 Tope End of File...

Page 99: ...Dallas Texas 75219 Chicago 1 inOIS 6063 214 528 6580 312 693 6060 2300 West Loop South Clausen Bldg Suite 310 Suite 150 16000 W Nine Mile Road Houston Texas 77027 Southfield Michigan 48075 713 623 05...