Manual / Guide · 1969
The service manual for the EC-1115: specifications, key functions, worked calculating methods, the Hitachi HD3100 chips, register operation, the anode charge-pump and cathode control circuits of the 12-tube Nixie display, power supply, troubleshooting and flow charts.
1115 ELECTRONIC CALCULATOR SERVICE MANUAL SINGER FRIDEN DIVISION TPD-I69SL 1115 ELECTRONIC CALCULATOR PREFACE The intent of this manual is to provide maintenance information to trained field personnel. When used for training pur- poses, this manual must be supplemented with a course curriculum. The manual itself is not designed for self in- struction. TPD-169SL eee, 1115 ELECTRONIC CALCULATOR CONTENTS PAGE SECTION 1. GENERAL DESCRIPTION A. APPEARANCE 1-1 B. SPECIFICATIONS 1-1 C. KEY FUNCTIONS 1-2 Digit Keys 1-2 Arithmetic Keys 1-2 Data Handling Keys 1-4 Power Switch 1-5 Indicating Lights 1=5 SECTION 2. CALCULATING METHODS A. GENERAL 2-1 B. ADDITION 2-1 C. SUBTRACTION 2-2 D. MULTIPLICATION 2-3 E. CONSTANT MULTIPLICATION 2-5 F. DIVISION 2-6 G. CONSTANT DIVISOR 2-7 H. ROUND OFF AND TRUNCATE 2=9 I. COMBINED CALCULATIONS 2-11 SECTION 3. LOGIC ELEMENTS A. COMPOSITION OF FUNDAMENTAL CIRCUIT 3-1 HD 3101 (Dual 8-bit Shift Register) 3=1 HD 3103 (5 MOS FET's) 3-2 HD 3104 (Dual 4-input AND gate, plus 2 Inverters) 3-2 HD 3106 (Dual 2- or 3-input AND/OR gate) 3-3 HD 3107 (4 "D" type Flip-Flops) 3-3 HD 3109 (60+4+4 Bit Dynamic Shift Register) 3-4 HD 3112 (Full Adder and Subtracter) 3-5 HD 3115 (RSS Flip-Flop) 3-6 OR Gate 3-7 SECTION 4. FUNCTIONAL DESCRIPTION A. GENERAL B. OPERATION OF EACH REGISTER Register Contents Shift Pulse and Timing Operation of TC Counter C. BASIC MACHINE OPERATION Development of the Fundamental Operation Display Condition-——-Circulation Calculating Condition--Circulation | I Gu nb FPWNRE aS si a Oe vei 12-29-69 4 TPD-169SL 12-29-69 SECTION 4. SECTION 5. A. B. C. D. E. F. H. a a J. SECTION 6. A. B. Cc. D. E. 1115 ELECTRONIC CALCULATOR CONTENTS (Cont. ) FUNCTIONAL DESCRIPTION (Cont.) Right Shift (RSH) Left Shift (LSH) Exchange (CHG) Add and Subtract (AOS) Complement (CWF) Three Register Operation Entry Data Add or Subtract Mult Divide 3-Register Calculation Using Examples Display Anode Control Circuit Cathode Control Circuit Input Circuits Master Oscillator and Clock Pulse Generator Power Supply Auto Clear MAINTENANCE GLOSSARY OF SIGNAL NAMES & LOGIC EQUATIONS DISASSEMBLY AND ASSEMBLY INSPECTION PROCEDURES OPERATIONAL CHECK TROUBLESHOOTING ADJUSTMENTS Keyboard Power Supply Power Supply Schematic + COMPONENT IDENTIFICATION & LAYOUT Printed Circuit Board Number Indicating Tubes Transistors Diodes PC Board Connector Assembly External Terminal Number Identification PRINTED CIRCUIT CARDS & COMPONENT LISTS POWER SUPPLY WIRING DIAGRAM WIRING LISTS & SIGNAL NAME CROSS REFERENCE FLOW CHARTS ENTRY ADD OR SUBTRACT MULT DIVIDE M, D, +, == it PAGE : a en es es NroOWwWOC oO ae i eee ae ee Nm bh we 4-26 TPD-169SL 1115 ELECTRONIC CALCULATOR SECTION 1 GENERAL DESCRIPTION SECTION CONTENTS PAGE A. APPEARANCE i=1 B. SPECIFICATIONS 1=1 C. KEY FUNCTIONS 1=2 DIGIT KEYS 1=2 ARITHMETIC KEYS 1-2 DATA HANDLING KEYS 1-4 POWER SWITCH 1-5 INDICATING LIGHTS 1-5 12-29-69 i TPD-169SL A. APPEARANCE OVF Light Top Cover i oe 1115 ELECTRONIC CALCULATOR GENERAL DESCRIPTION Display Sign Indicator Light Round off Switch Function Bottom Keys Cover 10-Key Keyboard Decimal Switch Power Switch FIGURE 1-1 The 1115 Electronic Calculator (Figure 1-1) is a small, light weight, high speed portable desk calculator featuring: a 12-digit Nixie type, number indicating tube display, 10-key keyboard, and integrated (IC) electronic circuitry for long life and maximum reliability. B. SPECIFICATIONS Size: Weight: Keyboard: Decimal System: Speed: Reliability: Power Source: Power Consumption: Ambient Temperature: 12-29-69 10" wide, 13' deep, and 4" high (approx). 10 lbs. 10-key type. Any number can be entered (maximum of 12 digits) using the ten digit keys (0-9) and the Decimal Point key if applicable. The Function keys are arranged around the Digit keys in a manner that provides maximum operator facility and ease of operation. Floating Input/Fixed Output (Decimal Switch Positions: 0, 2, 5) The longest arithmetic problem in: Addition and Subtraction 0.05 sec. Multiplication 0.4 sec. Division 0.4 sec. Use of the latest state of the art integrated circuit chips, transistors, and diodes insures maximum reliability and service- ability. The 1115 can be connected to any standard, grounded 115 VAC out- let. Transformer taps are provided for 100V, 110V, 117V, & 120V (50/60 Hz) operation. Optional voltages are available on special order. 12 watts 0-40° C (32-104° F) 1-1 TPD-169SL 1115 ELECTRONIC CALCULATOR GENERAL DESCRIPTION C. KEY FUNCTIONS The Keyboard keys (Figure 1-2) can be grouped by function as: Digit, Arithmetic, and Data Handling. The Digit keys are used in entering numbers; the Arithmetic keys are used in operations which involve computations; and the Data Handling keys shift numbers between registers, or clear numbers from the machine. Display (Nixie Tubes) (12) Sign Indicator Light Overflow Light Minus Equal Key Constant Key Divide Key Round Off Key Clear Entry Key Reverse Key Dec, Switch Mult Key Power Switch Plus Equal Key Clear Keys Decimal Point Key Digit Keys (10) FIGURE 1-2 1. DIGIT KEYS Numbers are entered into the 1115 data loop digit-by-digit by use of the digit keys. Since numbers can contain decimal digits, the decimal point key is also con- sidered to be in the digit group because it is used for a decimal number entry. 2. ARITHMETIC KEYS The arithmetic keys enable and initiate the arithmetic operations that will be performed with and on the numbers. Briefly their functions are: a. PLUS EQUAL KEY. Depression of this key initiates the addition, multiplication, and division functions. In an Add function the contents of R2 are added to R3. In Mult or Divide, the answer is produced in R2 as a result of repeat addition or repeat sub- traction. += When the machine is not conditioned to multiply or divide, depression of this key causes R2 to be added to R3 with the re- sult in R2 and the 2nd Entry to be retained in R3. (Note: In the 1115, the 2nd Entry will always be retained in R3 following an Add, Subtract, Mult, or Divide.) If the machine is conditioned to multiply and no data has been entered into R2 since the multi- ply conditioning, depression of this key causes: R2 to transfer to R3 with R2 being unchanged; R3 to be multiplied by R2; the final product in R2 and the entered number retained in R3. 12-29-69 2 TPD-169SL 1115 ELECTRONIC CALCULATOR GENERAL DESCRIPTION If the machine is conditioned to multiply and data has entered R2 since the multiply conditioning, R3 is multiplied by R2 with the product in R2 and the 2nd Entry retained in R3. If the machine is conditioned to divide, depression of this key causes R2 to be divided by R3 with the quotient in R2 and the 2nd Entry retained in R3. b. MINUS EQUAL KEY. Depression of this key initiates the sub- traction, multiplication, and division functions. When the ma- chine is not conditioned to multiply or divide, depression of this key causes R3 to be subtracted from R2 with the result in er R2 and the 2nd Entry in R3. If the machine is conditioned to multiply, multiplication occurs as defined for Plus Equal, ex- cept prior to multiplication, the sign of R2 is changed. If the machine is conditioned to divide, division will occur as defined for the Plus Equal key except prior to division, the sign of R2 is changed. c. MULT KEY. Depression of this key terminates the digit entry and conditions the machine to multiply. However, when the machine is already conditioned to multiply, or divide, by a prior Mult or Xx Divide key depression, and the Mult key is again depressed follow- ing a digit entry, the machine will perform the function correspond- ing to its prior conditioning. This will also establish a Mult con- dition for the next machine operation. d. DIVIDE KEY. Depression of this key terminates the digit entry and conditions the machine to divide. However, when the machine is already conditioned to multiply, or divide, by a prior Mult or = Divide key depression, and the Divide key is again depressed follow- ing a digit entry, the machine will perform the function correspond- ing to its prior conditioning. This will also establish a Divide con- dition for the next machine operation. e. DECIMAL SET SWITCH. This is a slide type switch having three positions for setting the decimal point at 0, 2, or 5. Decimal control of the final answer is defined by the setting of the Deci- mal Set Switch. f. CONSTANT KEY (K). This is a latch down type key used for retain- ing a constant multiplier or a constant divisor. It also retains K the command to multiply or divide until a Mult or Divide key is de- pressed to change the constant function. Briefly, the Constant key is used as follows: CxBe= C+Be= B3 Dx B= D+Be= Bt 12-29-69 1-3 TPD-169SL R Yo 1115 ELECTRONIC CALCULATOR GENERAL DESCRIPTION When the "K" key is in the latched position (down), the first step of each key function is normal as: A B 5) oA B f=] ; B is . After the first mult or divide key function is completed, the key function in use is automatically retained and the "B'" factor becomes a constant. Under this condition, entry of a new number (C or D) factor causes the contents of the pre- vious product in R2 to be cleared and the new entry (C or D) goes into R2 while the constant factor "B" is retained in R3. Depression of the [+4] key causes the second calculation to be performed. In other words, when the "K'"' key is latched down, depressing the S| key or the key always causes R3 to be multiplied by R2 (for the multiplication condition); or R2 to be divided by R3 (for the divide condition). The operation will continue in this manner until another Mult or Divide key is depressed. Then, the constant condition set up by the "K" key is cleared and normal machine operation is established even though the "'K" key remains latched down. g. ROUND OFF SWITCH. The Round Off Switch is a latch down type switch which enables a decimal round off of the LSD of the answer in R2 if necessary. When the R/O switch is latched down and the decimal number to the right of the LSD in R2 is greater than "4", a "1" is added to the LSD in R2. 3. DATA HANDLING KEYS Using the data handling keys results in the shifting of numbers between registers; and the clearing of numbers from R2 and R3. The function of the Data Handling keys is explained briefly as follows: R CE 12-29-69 a. REVERSE KEY. Depression of this key exchanges the contents of R2 and R3. The algebraic sign of a register is considered as part of its contents. b. CLEAR KEY. Depression of this key causes Rl, R2, and R3 to be cleared, and all control flip-flops will reset. If the machine is in an overflow condition, the overflow light will be turned off and the keyboard will be unlocked electrically. c. CLEAR ENTRY KEY. Depression of this key causes R2 and Rl to be cleared. If the machine is in an overflow condition, the over- flow light will be turned off and the keyboard will be unlocked electrically. 1-4 TPD-169SL 1115 ELECTRONIC CALCULATOR GENERAL DESCRIPTION 4. POWER SWITCH A push-on, push-off type switch located in the lower left corner of the keyboard is used to turn the power on and off. Turning the machine power on automatically causes all registers to be cleared to zero, the sign of all registers to be positive, and the decimal position of all registers to be transferred to the right of the lowest displayed ordinal position. 5. INDICATING LIGHTS a. OVERFLOW LIGHT. The Overflow light located at the left side of the display panel comes on: (1) When data entry to R2 exceeds 12 digits or 11 decimal digits. (2) When the integer portion of the answer developed in R2 minus the number of decimal places defined by the Decimal Switch exceeds 12 digits. When the overflow condition is indicated, the keyboard is immediately interlocked electrically. The overflow condition is cleared by the Clear key or the Clear Entry key. b. NEGATIVE LIGHT. The Negative Light located at the right side of the display panel comes on: (1) When the data is entered in R2 by the Minus Equal key. (2) When the output (answer) is negative (as governed by the rules of algebraic signs). 12-29-69 i-5 TPD-169SL a cy 12-29-69 1115 ELECTRONIC CALCULATOR SECTION 2 CALCULATING METHODS SECTION CONTENTS . GENERAL . ADDITION . SUBTRACTION . MULTIPLICATION . CONSTANT MULTIPLICATION DIVISION . CONSTANT DIVISOR . ROUND OFF AND TRUNCATE . COMBINED CALCULATIONS PAGE 2-1 2-1 2-2 2-3 2-5 2-6 2=7 2-9 2-11 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS A. GENERAL This section of the manual describes the various calculations possible with the 1115 Electronic Calculator. Sample problems are provided to illustrate the process and to give the CSRep a working knowledge of the machine operation which is essential to understanding the machine logic and an aid in troubleshooting. Listed below are several pertinent points that should be noted. (1) The machine has a floating decimal point input and a fixed point output system. (2) When an answer or ar entry is negative, it is indicated with a minus sign. (3) The number recalled by the Reverse key is used the same as a digit entry. (4) Repeated depression of the Mult and Divide keys merely changes the order of the operation to coincide with the last depressed key, B. ADDITION Addition is accurate up to 12 digits. Depressing the Clear key is necessary be- fore each calculation. PROBLEMS : (1) Addition without decimals under decimal preset position of 2. 946 + 583 + 123 = 1652.00 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 946+583+123=1652 sh R/o|+ [C] 946 +=] 946 .00 583 += 1529.00 123 += 1652.00 12-29-69 Z=1 TPD-169SL B. ADDITION (Cont.) CALCULATING METHODS 1115 ELECTRONIC CALCULATOR (2) Addition with decimal under decimal preset position of 2. 2.63 + 0.574 + 0.02 = 3.22 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 2 2) 2.63+0.57+0.02=3.22 : R/O} + [C! 2.63 += 2.63 0.57 ia 3.20 0.02 iz 3.22 C. SUBTRACTION Subtraction is accurate up to 12 digits. before each calculation. PROBLEMS: (1) Subtraction without decimals under decimal preset position of 2. Depressing the Clear key is necessary 12-29-69 2-2 657 - 492 = INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 657 - 492 = 165 hin R/O|* ([C] | 657 += 657.00 492 -= 165.00 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS C. SUBTRACTION (Cont.) (2) Subtraction and Addition under decimal preset position of 2. -530 + 829 = 299.00 (3) Subtraction with True Credit Balance under decimal preset position of 2. 139 - 567 = -428.00 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 2 2) -530 + 829 = 299 R/O} + 530 r 530.00- 829 +3] 299.00 L_| 2 3) 139 - 567 = -428 su R/O| + 139 139.00 567 = 428.00- LJ DC. MULTIPLICATION Multiplication is accurate up to 12 digits and depressing the Clear key is not ne- cessary before each calculation. In chain multiplication (and regular multiplication) if the integer portion of the result developed by multiplying the previous product and the next multiplier exceeds 12 digits (minus the decimal preset number) it will be necessary to set the decimal set switch to "0". In Chain Multiplication, successive products can be multiplied with or without using the Plus Equal key each time. For example: 123 x 456 x 789 +. 12-29-69 2-3 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS D. MULTIPLICATION (Cont. ) PROBLEMS : (1) Multiplication without decimals 12 x 24= 288 (2) Multiplication with decimals 6.123 x 47.89 = 293.23047 (3) Chain multiplication 3.69 x 65.41 x 1.479 = 356.97572 (4) Multiplication with negatives -369 x 682 x (-34) = 8556372 12-29-69 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 12x24 = 288 sh R/O] 4 12 X 12. 24 +: 288.00 2) 6.123x47.89 ii R/O] + 6.123 6.123 47.89 + 293.23 3) 3.69x65.41x1.479 hn R/O} + = 356.9757291 3.69 3.69 65.41 [x] 241.36 1.479 “4 356.97 or another way ih R/O} ¥ 3.69x65.41 = 241.36 3.69 3.69 65.41 a 241.36 241.36x1.479 = 356.97 xX] 241.36 1.479 356.97 4) -369x682x(-34)=8556372 ih r/o} ¥[C | 369 Ks 369.00 x] 369.00 682 Ei 251658.00 34 -= 8556372 .00 a 2-4 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS E. CONSTANT MULTIPLICATION The Constant key "K" is used for this calculation. Normal operation, except Add and Subtract, can be accomplished even though the "K" key is latched down. See page 1-3 for an explanation of the "K" key operation. PROBLEMS : GROUP 1 (1) 123 x 4.56 = 560.88 (2) 563 x 4.56 = 2567.28 (3) 213 x 4.56 = 971.28 Note: The number "4.56" is the constant multiplier GROUP 2 (Involution) (1) 25° = 625 (2) 25° = 15625 (3) 25° = 390625 Note: In this case, the constant multiplier is "25". INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 123x4.56=560.88 in R/o|+ [Ky 123 - Xx) 123: 4.56 + 560.88 563x4.56=2567.28 563 r= 2567.28 213x4.56=971.28 213 = 971.28 2) 25 = 625 25 [x] 25. + 625.00 25° = 15625 : 15625 .00 25° = 390625 +: 390625 .00 12-29-69 2-5 [PD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS F. DIVISION Division is accurate up to 12 digits. Touching the Clear key is not necessary be- fore each calculation. In chain division, successive quotients can be divided without using the Plus Equal key each time. PROBLEMS : (1) Division without decimals 145 + 12 = 12.08333 (2) Division with Decimals 4962.184 + 13.2 = 375.92303 (3) Chain Division 369 + 123 + 456 = 0.00658 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 145:12=12.08333 sth R/0| + 145 a 145. 12 + 12.08333 2) 4962.184:13.2 4962.184 [=] 4962.184 =375.923030 13.2 += 375 .92303 3) 369:123:456 369 [=] 369. =0.006578 123 a 3.00000 456 += 0.00658 Or another way 369:123=3 369 Fl 369. 123 += 3.00000 3:456=0.006578 a 3.00000 456 fs 0.00658 12-29-69 2-6 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS G. CONSTANT DIVISOR The Constant key "K" is used for this calculation. Normal operation, except Add and Subtract may be accomplished even though the "K" key is latched down. See Page 1-3 for an explanation of the "K" key function. PROBLEMS : (1) 297 + 1364 = 0.21774 (2) 6428 + 1364 = 4.71261 (3) 1000 * 1364 = 0.73314 Note: The number "1364" is the constant divisor. (4) 12367 = 1030.58333 12 (5) 12367 = 85.88194 122 (6) 12367 = 7.15683 123 Note: The number "12" is the constant divisor. INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 297:1364=0.21774 297 [=] 297 1364 =| 21774 2) 6428:1364=4.71261 6428 2 4.71261 3) 1000:1364=0.73314 1000 + 73314 4) 12367 1030.58333} 12367. °«#=| ~~ |?) | 12367. | ~~ T2— 12 fa 1030.58333 12-29-69 2-7 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS G. CONSTANT DIVISOR (Cont.) SOLUTION INDEX IN KEYBOARD TOUCH FUNCTION KEYS IN SEQUENCE DISPLAY 5) 12367 = 85.88194 rs 12 6)12367 12 7.15683 += ia 85.88194 7.15683 12-29-69 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS H. ROUND OFF AND TRUNCATE Round Off and Truncate action is performed on the digit to the right of the digit in the lowest decimal position displayed. The answer will be rounded off or truncated depending on the position of the Round Off Switch. That is, in a Round Off calculation, the Round Off Switch must be preset to the position of R/O prior to starting the cal- culation. If the Round Off Switch is not preset to the position of R/O, the answer will be truncated instead. Also, if the decimal digit numbers of the entry are greater than the Decimal Switch setting, the entry number will be rounded off or truncated by depression of the Plus Equal key. The number displayed will be defined by the Decimal Switch setting. PROBLEMS: (Decimal Switch set at "2") (1) Addition and Subtraction under round off condition. 5.372 + 17.369 - 1.234 = 21.51 (2) Multiplication and Division under round off and truncate condition. 45.769 x 3.52 = 161.11 Rounding Off 45.769 * 3.52 13.00 45.769 x 3.52 161.10 Truncate 12-29-69 2-9 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS H. ROUND OFF AND TRUNCATE (Cont.) 12-29-69 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 5.372+17.369-1.234 R/O] ¥/C cis =21.51 5.372 Ke 5.37 17.369 = 22.74 1.234 ry 21.51 2) 45.769x3.52=161.11 ih R/O] ¥ L__J 45.769 xX] 45.769 3.52 += 161.11 3) 45.769x3.52=161.10 R/O] + 45.769 X 45.769 3.52 p= 161.10 4) 45.769:3.52=13.00 | 45.769 [Fl 3.52 += 13.00 2-10 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS I. COMBINED CALCULATIONS Examples of combined calculations are shown in the three problems that follow. PROBLEMS : (1) 123 x 45.6 + 78.9 - 1.47 + 25.76 = 95.3774 (2) 1000 (160+320+102) (3) (140.05)? -1 = 1.7182 x 12300 = 67965.264375 0.05 INDEX IN TOUCH FUNCTION KEYS SOLUTION KEYBOARD IN SEQUENCE DISPLAY 1) 123x45.6:78.9-1.47 it R/O} + +25.76=95.3774 123 [x] 123. 45.6 a 5608.80 78.9 += 71.09 1.47 F| 69.62 25.76 ia 95.38 2) 1000 = 1.7182 ain R/O| +|C +320+ 160 +2 160.00 320 a 480.00 102 a 582.00 [=] 582.00 1000 R 582.0C + i ly fs 12-29-69 2-11 TPD-169SL 1115 ELECTRONIC CALCULATOR CALCULATING METHODS I. COMBINED CALCULATIONS (Cont.) INDEX IN TOUCH FUNCTION KEYS SOLUTION EYBOARD IN SEQUENCE DISPLAY 3) (140.05) - 1x 12309 inh R/Ov | K]+[ C] 0.05 = 67965.264375 1 +a 1.00000 0.05 +=] 1.05000 — X 1.05000 +3 1.10250 pen +2 1.15763 fr 1.21551 +=! 1.27629 L_| TK] 4 1.27629 Lo 1 r 0.27629 a 0.27629 0.05 X 5.52580 12300 f= 67967.34000 12-29-69 2-12 TPD-169SL 1115 ELECTRONIC CALCULATOR SECTION 3 LOGIC ELEMENTS SECTION CONTENTS PAGE A. COMPOSITION OF FUNDAMENTAL CIRCUIT 3-1 HD 3101 (Dual 8-bit Shift Register) 3-1 HD 3103 (5 MOS FET's) 3-2 HD 3104 (Dual 4-input AND gate, plus 2 Inverters) - HD 3106 (Dual 2- or 3-input AND/OR gate) HD 3107 (4 "D" type Flip-Flops) HD 3109 (60+4+4 Bit Dynamic Shift Register) HD 3112 (Full Adder and Subtracter) HD 3115 (RSS Flip-Flop) OR Gate ee te Ge Ge ae ie NOU L WW hd 12-29-69 i TPD-169SL 1115 ELECTRONIC CALCULATOR LOGIC ELEMENTS A. COMPOSITION OF FUNDAMENTAL CIRCUIT The logic circuits of this machine are composed primarily of eight types of MOS (Metal Oxide Semiconductor) IC (integrated circuit) packaged in dual-in-line circuit chips. Other circuits in the machine are composed of discrete components such as diodes, transistors, etc. Shown in the Table below are the 8 MOS IC chips used in the machine and their circuit function. A brief explanation of each chip is also included here to famili- arize the CSRep with their general function. Type of IC Circuit Function 4D 3101 dual 8-bit quasi-static shift register HD 3103 five MOS FETs (Inverters) HD 3104 dual 4 input AND gate + two inverters HD 3106 dual 2 input & a dual 3 input AND gate HD 3107 quadruple quasi-static D type flip-flop HD 3109 60 + 4+ 4 bits dynamic shift register 7 (with control gates) HD 3112 delayed full adder HD 3115 triple quasi-static RSS flip-flop 1. HD 3101 (Dual 8-bit Shift Register) A dual 8-bit shift register which is connected in a series configuration to form a 16-bit shift register as shown in Figure 3-l. WwRoT 2 [fst Lipsy > |] 2 ouTPUT ont — T i r ui re“! SSITS ++ 84 OBITS 9 bee --7-- e's a | 5 al CPa CP2 cP4 HD 3101 FIGURE 3-1 12-29-69 3-1 TPD-169SL 2. HD 3103 (5 MOS FET's) LOGIC ELEMENTS 1115 ELECTRONIC CALCULATOR This IC contains 5 MOS FET's which are used as inverters (Figure 3-2) or as trans- fer gates (Figure 3-3). INVERTER TRANSFER GATE outl out2 out3 out4 outd5 FIGURE 3-2 outl out3 out} out4 out5 ia ‘ ’ 1 . -t 5 J. ae AN ‘ x ‘ S 3 . 4 s uf ‘ ' 1 ayer? fpr! binrd ‘ ' ' od ‘= SQ AW ' : ie H og + %& ey 1 \ ' ‘ ew <ee HBBAR HD 3103 FIGURE 3-3 3. HD 3104 (Dual 4-input AND gate plus 2 Inverters) This IC is composed of dual 4-input AND/OR gates operate as AND circuits when Logic 1 corresponds to when Logic 0 correspond to "0" volts (Figure 3-4). outl 9 out2 outs out4 sok ‘ ‘ ways fe a ’ / ) ‘ ' ' ‘ L --- - B 12-29-69 de Lp A3 A4 B2 D2 HD 3104 FIGURE 3-4 3-2 out 1=Al out 2=A2 out 3=A3 out 4= A4 out 5=A5 out 1=Al- Bl out 2=A2° B2 out 3=A3+ B3 out 4=A4>+ B4 out 5=A5+ BS and 2 Inverters. "QO" volts and operate as OR gates i 7 out 1=Al+Bl+Cl- Dl sot Sia phe. out 2= A2 »- B2* C2 D2 \ out 3= A3 i | out 4—= A4 The gate circuits TPD- 169SL 1115 ELECTRONIC CALCULATOR LOGIC 4. HD 3106 (Dual 3-input AND/OR gate and ELEMENTS Dual 2-input AND/OR gate) This IC is composed of dual 3-input AND/OR gate circuits and dual 2-input AND/OR gates which are used extensively in the various logic circuits of the machine (Fig- ure 3-5). outl out2 ii | _ outl=Al> Bl WA . ! out2=A2+B2 out3=A3+-B3°C3 out4=A4+B4-C4 so od OT Uf Al Bl A2 B2 AZ |C3 Ad] C4 B3 B4 HD 3106 FIGURE 3-5 5. HD 3107 (4 "D" type Flip-Flops) This IC is composed of 4 "D" type FFs which can be used as individual flip-flops or if connected in series, can be used as a 4-bit shift register (Figure 3-6). 02 [ f CP1 — EUV TN —— == oe CP2 Connections for operation as a 4-bit shift register are as follows: O010UT —___ | 01 to I2 Independent "D" type 02 to I3 Flip-Flop Operation 2, to I HD 3107 . FIGURE 3-6 12-29-69 3-3 TPD-169SL 1115 ELECTRONIC CALCULATOR LOGIC ELEMENTS 6. HD 3109 (60 +4 +4-Bit Dynamic Shift Register) This IC is called a Medium Scale Integrated Circuit (MSI) and contains a 68-bit shift register (60 + 4+ 4). That is, the IC can retain 68 bits of data consisting of 17 4-bit (BCD) digits in a dynamic shift register (Figure 3-7). CEolga Cantap 4p 16 17 18 19 20 60 : 3 a rrcrcctcccce a! ote--a 8 permet 7m o— 7 “ ’ ; ¢ ' ': 4 ji oe ' Pog ay tsa ty Renee | 2 6 6J°4 60 bits f “ibit’ “bid =a : nn a iat “er 7 ~ Ges f UO cee = ati adlce etl ed RC Or PH ' ' { ’ = Ses Sea ' 3] 1 a | 2 CPiq CP2 CPip HD 3109 FIGURE 3-7 ADD BASIC FAS TRUTH TABLES SUB FA | FC FA |FC x | y | c jour] IN x | y | c [OUTIJIN oj;f[olo|lolo ololololo 1{folo];i1ifo 1lojlo/;1ijo ofi{fof{i{o of1}]of{1]1 1/ivoftojl 17Tilvlofolo o;/ofififo ofo;ifilfil 1/oflifofil i/ofifofo o;fivifojfi ofiflifoji1 1/i/i1jf1i1f1 1/ivyijyilfil X = X input FA OUT = SUM ADDER OUTPUT Y = Y input FC IN = CARRY ENABLE INPUT C = CONDITION OF CARRY (FC) ADD FAS COMPENSATION TRUTH TABLES SUB BI4 BT4 HC Loe XC1|Ff |HC |Xo |ENABLE XC1|F£ |HC |Xo ABLE ofolflol!fo 0 olfololo 0 1]/o}]o]1 0 1{[olo]jl 0 o{[1]/o]1 0 o/1i1]/oj1 1 1}/1i]0o0]0 1 1/1 {/o0]0 0 ofof;filfil 0 ofojtilfil 1 1/o{l11/0 1 1/0/1110 0 GLlri zis 1 o{1]140 t BEES E: 1 1Jijfifi 1 XCl = LSD OF DIGIT FROM 4-BIT REGISTER XO = COMPENSATION ADDER OUTPUT Ff = OUTPUT OF COMPENSATION FLIP-FLOP. HC ENABLE = CARRY ENABLE INPUT HC = OUTPUT OF COMPENSATION CARRY FLIP-FLOP. AT BT4. (NOTE: CARRY CANNOT BE ENABLED AT BT4 TIME.) 12-29-69 3-4 TPD-169SL 1115 ELECTRONIC CALCULATOR LOGIC ELEMENTS 7. HD 3112 (Delayed Full Adder) This IC is a Medium Scale Integrated Circuit (MSI) and performs as a series delayed Full Adder/Subtracter. Figure 3-8 shows the HD 3112 IC as it is used in the EC 1115 machine. (FAS Add and Subtract Truth Tables are illustrated on page 3-4.) FULL ADDER & SUBTRACTER @) (HD 3112) xC4 xC3 XC2 nN aN 1 CPI CPl xc-4 LOH xc-s LO xc-2 re Oe I Po oT or =a HC oo Ha a —_ 7 = — CPp2 CPp2 CPp2 Cp2 (COMP. CARRY) a (COMPENSATION) ADDER Ff T(-24V) (SUM CARRY) —/ HC | te >t a CPl CP2 « : ~24V . F Ain TEN) (CARRY ENABLE) . 18 os FC = > —9 5 — s CPi] po |CP2 aE +2 C= CARRY (FC) or a Facet A= ADD. (FASSUB) Fe a 3 cS) e¢ fee penn 5 be & S= SUBT. (F ASSUB) | < CARRY) o = _- — FCin (BLOCK CARRY) 6 BT4 (SUM ADDER) (CARRY ENABLE) S4 cl C2 C3 C4 x¥c eee Axy| |sxc| Jaxc Cp2 T T T tT ] a YY 2 CPl CP2 FASSUB *REFER TO Ge< |] 5 SS); oy Lee LOGIC SCHE- x mn | x MATIC FOR CONTROL SIGNAL A® 8 « @i) + EC1115 oO be ‘FassuB \o 6 /\G2) \ “ a X(al) Y¥ (a2) HD 3112 FIGURE 3-8 12-29-69 3-5 TPD-169SL 1115 ELECTRONIC CALCULATOR LOGIC ELEMENTS 8. HD 3115 (RSS Flip-Flop) This MOS IC contains 3 RSS type flip-flops so designated because of the set-reset control logic which acts in the following manner. (1) With a false input to the set and reset inputs, the output of the FF does not change when triggered. (2) With a false input to the set input and a true to the reset input, the FF will transition to the reset (true) condition when triggered. (3) With a true to the set input and a false to the reset input, the FF will tran- sition to the set (true) condition when triggered. (4) With a true at both the set and reset inputs, the FF will set if it was reset, but it does not toggle under this condition. The IC is shown in the diagram (Figure 3-9) below, along with its truth table. logic table for R-S-S flip-flop 0} 01 02 Oo 03 03 SET SIDE ? iP Ff ? INPUT | OUTPUT [ - S_|R 0 pars, EA AS Qo | 0 Qn_| (WO CHANGE) jeich Eg rs o |i [0 aa SY a Fa 1 10 1 Hh. oe 1 ta 1 ——+ ; 2 T _d| o| o o 6 cpl} R1J S2 R2 S3 RB Sl cp2 “LF LF LOL “TLE LU Lu Ss we | | -— R INPUT ne es Q OUTPUT Q OUTPUT | HD 3115 FIGURE 3-9 12-29-69 3-6 TPD-169SL 1115 ELECTRONIC CALCULATOR LOGIC ELEMENTS 9. OR GATE OR gates in this machine are composed of discrete components (diodes) arranged as shown in the illustration below (Figure 3-10). (NOTE: Diode packs (HD9001) containing 4 diodes are also used.) mw Q BIR IO;O|> Hlo|Hlo|s BHR lOola -24V OR GATE "OR' TRUTH TABLE FIGURE 3-10 12-29-69 3-7 TPD-169SL 12-29-69 1115 ELECTRONIC CALCULATOR SECTION 4 FUNCTIONAL DESCRIPTION SECTION CONTENTS A. GENERAL B. OPERATION OF EACH REGISTER REGISTER CONTENTS SHIFT PULSE AND TIMING OPERATION OF TC COUNTER C. BASIC MACHINE OPERATION DEVELOPMENT OF THE FUNDAMENTAL OPERATION Display Condition--Circulation Calculating Condition--Circulation Right Shift (RSH) Left Shift (LSH) Exchange (CHG) Add and Subtract (AOS) Complement (CWF) THREE REGISTER OPERATION Entry Data Add or Subtract Mult Divide 3-Register Calculation Using Examples DISPLAY Anode Control Circuit Cathode Control Circuit INPUT CIRCUITS MASTER OSCILLATOR AND CLOCK PULSE GENERATOR POWER SUPPLY AUTO CLEAR PAGE COnNNAAUU TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION A. GENERAL In Figure 4-1 is shown a block diagram of the 1115 Electronic Calculator indicating the data flow through the registers. A brief explanation of the block diagram and associated control circuits is included here to aid in understanding the operation of the machine. Display Circuit | a bits 1\4—b1 ; RINAAT | by = Eis Yin Ri N) 3 Rl (60 bits) R2 (64 bits) Yin Ee Rlin R2in >O—> R3 (64 bits) J | TC (16 bits) [> R3in +1 Entry | Control Clock Pulse Power Supply | = Circuit | Circuit Generator Circuit 1115 BLOCK DIAGRAM FIGURE 4-1 FAS: Full Adder/Subtracter (includes R1N13 consisting of 4-Bits). RIN14: 4-Bits of Rl Register used only in a left shift operation. R2: Entry input and output (answer). Also used in series with Rl for dynamic data flow and during calculation to develop the answer in conjunction with the other two registers (Rl & R3) and FAS. (64 bit dynamic shift register.) R3: Factor Register (64 bit dynamic shift register). LCs Counter (16 bit static shift register). B. OPERATION OF EACH REGISTER Each register stores data in a unidirectional shift flow. That is, data flow is dynamic and serial in the form of binary coded decimal (BCD) information. Data is organized into Word times, Digit times, and Bit times under control of the clock pulses: CP1l CP1l. CP2, BT4CP1, WICP1, and WT2CP1. 12-29-69 4-1 TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION B. OPERATION OF EACH REGISTER (Cont.) Entry data and the result (output) is retained in R2 and the output data from R2 is gated into the input of R2 to form a loop. At the same time that R2 data is re- circulated into its own input gate, it is parallel shifted into the Full Adder and Subtracter (FAS). Then the BCD data output from FAS is gated into a decoder circuit to the Indicator Nixie Tubes for display. During the time R2 data is being displayed via the output from FAS, the data loop between FAS and register Rl is open and the contents of FAS and Rl are eliminated. However, when the machine is in a calculating operation, the output of Rl is connected to the input of R2 to form a double iength register of 32 digits (128) bits. (Note: RIN14 is used only during a left shift, therefore, its output is open.) 1. REGISTER CONTENTS In this machine, a decimal point counter and sign flip-flop are not used. Instead, the decimal point and sign information are stored within specific positions in the register. That is, each register consists of 64 bits (16 digits) and registers R2 and R3 are divided into segments having 56 bits, 3 bits, and 5 bits. The portion of the register having 56 bits is used for retaining the arithmetic data. The next portion having 3 bits is used for retaining the sign data; and the portion having 5 bits is used for retaining the decimal point data. The relative position of the 3 segments of the register is shown in Figure 4-2. Starting at the right end of the register each segment is explained as follows: R2 (64 bits) ~ f i | R2in —> |!: ara at r it ——_ eee eS ee ewe ee ee it at i TT T Um : ‘if, ' ' —= R2out ——— lee ih al T ! t ‘ i Let ooad be eo ee ——— ' ' ‘ ’ a eG, Se ee ee ert R2N | Ros R2N)]-- eee eee eee es -RAN3 R2N] R2Na REGISTER CONTENTS FIGURE 4-2 R2P (5 bits): Contains information defining the decimal point position of the number to be displayed. R2S (3 bits): Contains the sign data which is defined as "000" for positive and "100" for for negative. R2N (56 bits): Contains the binary coded decimal (BCD) information representing the arithmetic data. R2NO (4 bits): Used when calculating a Round Off. R2N-1VN-12: The contents in this position represents the 12 digits to be displayed. R2N-13: The 4 bits in this position are used in the dynamic data loop and also to detect an overflow condition. 12-29-69 4-2 TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION 2. SHIFT PULSE AND TIMING In this machine, the following shift pulses and timing pulses (Figure 4-3) are used. Timing Pulse: WT1, WI2, DT1 through DT16, and BT1 through BT4. Clock Pulses: CP1, CP2, BT4CP1, WICP1, WI2CP1, and CPl. NOTE: WT1+WT2 is equal to one word time and there are 128 shift pulses generated during each word time. Each shift pulse corresponds to one bit time in the register. chm TUNNEY UU ULL epi = TIMNNTOTOvOnim ~~~ ~~ TTTTITITNNT ~~~ --THTTTTTTITTTT BT3 fL_J_JL_---------- LL J----- ---LILn BT4 Ml f_f--------: 1 JLJL------- JL JL sacri TTP TTT TTT DTI ee DT2 oan eee waded! ee JL WICP1 TO 7 yt WT2CP1 Be a wTl oe rs ~~ Led WT2 pe es nn TIMING WAVEFORMS FIGURE 4-3 12-29-69 4-3 TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION 3. OPERATION OF TC COUNTER The TC Counter is a 16-bit counter (corresponding to the information in one regis- ter) used for controlling the shifting of data during a Mult or Divide operation. For example, when the MDF FF is set indicating a Mult or Divide operation the right or left shift enabling logic to Gate 17 will cause an input pulse to the TC counter each WT1.DT1 time. Also, each time Gate 17 is enabled, it enables Gate 16 and the TCCP1 shift pulse will increment the TC Counter. When a Mult or Divide operation is not being performed, Gate 17 is inhibited and Gate 16 is enabled via the signal MDF, therefore, the TC Counter will be cleared. output TC=16 input;-—16(bits)static shift registen a TCCP 17 CCP1 VGG -24V I 16 ma Bit oO j AN | 4+ oF i = rE as ~ ate ratare RSH : right shift LSH : left shift MDF : output in multiplication and division TC COUNTER FIGURE 4-4 C. BASIC MACHINE OPERATION A general description of the EC 1115 operation covering the: 3-Register Calcula- tion, Display Circuits, Input Circuits, Power Supply and Auto Clear Circuit, and Master Oscillator and Clock Pulse Generator is included in this section of the manual. Data flow in the three registers of the 1115 is serial and dynmmic in step with the four bit times, BT1l, BT2, BT3, and BT4 developed in each digit time, and under control of the clock pulses, CPl, CP2, BT4CP1, WICP1, and WT2CP1. A complete data loop via Rl and R2 consists of 32 digits (128 bit pulses) under control of the Clock Pulse Generator. 12-29-69 4-4 TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION C. BASIC MACHINE OPERATION (Cont.) The logic for the 1115 is similar to that of the 1114 but does not include the "Underflow" system, or the "Memory" storage. It does however, operate with a 3- register system, a Roundoff Feature, an Overflow system, a Fixed Decimal Point out- put controlled by a Decimal Switch, a Floating Point input system, and a Constant Multiplier or Divisor feature. 1. DEVELOPMENT OF THE FUNDAMENTAL OPERATION The fundamental operation of the 1115 concerns the data flow within the registers during the time of Display and during the time the machine is calculating. Both of these conditions will be explained in the illustrations and discussion that follow. The fundamental operation of the 1115 can be divided as follows: DISPLAY CONDITION--—CIRCULATION FUNDAMENTAL OPERATION CIRCULATION RIGHT SHIFT CALCULATING LEFT SHIFT CONDITION EXCHANGE ADD or SUB L ! 1N\4 FAS Rl L R2 aL DISPLAY CONDITION--CIRCULATION FIGURE 4-5 a. DISPLAY CONDITION--CIRCULATION. In a display condition without key operation (machine idling), the data mavement throughout the 3-registers is as shown in Figure 4-5. Output data from register R2 re-enters the input to R2 and at the same time it enters the "X" input to the full adder and subtracter (FAS). The Xo output between FAS and the Rl register is open and the FAS Xo output data is destroyed. The display outputs from FAS (FA, XC2, XC3, and xC4), however, are used to feed the display de- coder circuits and therefore, R2N data is displayed digit by digit as it enters FAS. The contents of R2 and R3 are retained in their closed loops, making two complete circulations each word time. 12-29-69 4-5 TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION =H CALCULATING CONDITION --CIRCULATION FIGURE 4-6 b. CALCULATING CONDITION--CIRCULATION. In a calculating condition, the circulation when not doing a right or left shift, exchange, or add or subtract function is as shown in Figure 4-6. During this circulation, the Xo output between FAS and Rl is closed, allowing data flow through Rl, R2, and FAS in a circulatory loop. The con- tents of register R3 are retained via the closed loop and two circulations of R3 are completed during one circulation of R1-R2-FAS. During the time R1-R2-FAS is circula- ting, the contents are being sensed in order to determine the next step of the function being performed. RETAIN POSITION RIGHT SHIFT (RSH) u FAS +> Rl me R2 FAS Rl = R2 (WI1.DT1.DT2.DT3) WT1.WI2.DT1.DT2.DT3 DEC. INFO.--SIGN--ROUNDOFF RIGHT SHIFT (RSH) Route of R2P.R2S.R2N during DT1 Route of calculated data during through DT3 of WTl time to re- DT4 through DT16 of WT1 and WT2 to tain the decimal and sign accomplish a right shift of one digit data in its proper position. position. RIGHT SHIFT FIGURE 4-7 c. RIGHT SHIFT (RSH). As mentioned previously, register R2 is divided into data segments designated R2N, R2P, and R2S with each segment retaining calculated data, decimal point data, and sign data respectively. In a right shift operation, the calculated data is shifted one digit position to the right. Since Rl is used for re- taining the entire calculated data, the contents of Rl and R2N must be shifted at the same time. On the other hand, since the contents of R2P and R2S must be retained without shifting data positions, the data in these two segments is routed in a dif- ferent circulatory loop than the calculated data. The routing and timing for the two conditions is shown in Figure 4-7. 12-29-69 4-6 TPD-169SL 1115 ELECTRONIC CALCULATOR FUNCTIONAL DESCRIPTION RETAIN POSITION LEFT SHIFT x _ x B FAS Rl R2 oe FAS -> Rl