DATAMATH CALCULATOR MUSEUM |
With the TMS0102 Texas Instruments introduced end of the year 1971 the first available standard calculator building block on a chip. The chip contains 3520-bit read-only program memory (320 words x 11 bits), a 182-bit random-access memory (44 x 4 bits, flags) and a decimal arithmetic logic unit as well as control, timing, and output decoders but no drivers for the display. This gives an overall complexity of roughly 5,000 transistors.
Due to a flexible design concept with both programmable PLA and ROM techniques a lot of design variations appeared. These include two different types of the key-matrix, 8 or 10 digits of 7- or 8-segmented outputs. Even the style of the numbers 4,6 and 9 varied among the family members.
A typical calculator built around the TMS0102 family performs the four basic functions +,-,*,: with either Constant or Chain operation. The calculations are done on a floating decimal-point operation but the display of the results could be selected between the floating-point or a fixed-point format. The keyboard scanning, debouncing and encoding in performed inside the chip. The display outputs are fully decoded with a leading zero suppression and multiplexed.
The family was later expanded with the TMS0123 design.
It took about a year till the first copy of the original design appeared. US based company Mostek introduced the MK5020P December, 1972.
The TMS0112 was produced in Japan by Toshiba, too.
Type | Calculator | Key-Matrix | Digits | Segment decoder | Timing |
TMS0101 | Canon Palmtronic LE-83 | [+],[-],[=] | 8 | LED | |
TMS0102 | Columbia II | [+=],[-=] | 8 | LED | |
TMS0103 | Bowmar 901B, JCE Mark II | [+=],[-=] | 8 | LED | |
TMS0105 | Canon L800 | [+=],[-=] | 8 | LED | |
TMS0106 | TI-3500, Canon L100S | [+=],[-=] | 10 | Panaplex | |
TMS0107 | Bowmar 901D | [+=],[-=] | 10 | LED | |
TMS0109 | TI-3000 | [+=],[-=] | 8 | Panaplex | |
TMS0110 | TI-2500 Preseries | [+],[-],[=] | 8 | LED | |
TMS0111 | Minimath prototypes | [+],[-],[=] | 8 | LCD | |
TMS0112 | Toshiba BC-0802 | [+=],[-],[=] | 8 | LED | |
TMS0115 | Panasonic JE-850U | [+],[-],[=] | 8 | LED | |
TMS0118 | [+],[-],[=] | 10 | LED | ||
TMS0119 | TI-2500, Heathkit IC-2108 | [+],[-],[=] | 8 | LED | |
TMS0719 | TI-2500 | [+],[-],[=] | 8 | LED | |
TMS1875 | Heathkit IC-2008 | [+],[-],[=] | 8 | LED |
Item | Min | Typ | Max | Unit | Comments |
VSS | 0 | V | |||
VDD | -8.1 | -7.2 | -6.6 | V | |
VGG | -13.2 | -14.4 | -16.2 | V | |
IDD | 17 | 25 | mA | ||
IGG | 10 | 15 | mA | ||
CK | 100 | 250 | 400 | kHz | Level between VSS and VGG |
The TMS0102 uses a
standard DIP-28 package.
Pin | IO | Function | Pin | IO | Function |
1 | I | Clock Input | 28 | V | Common Voltage |
2 | I | Keymatrix input P | 27 | I | Keymatrix input Q |
3 | O | Digit driver 1 (LSD) | 26 | I | Keymatrix input N |
4 | O | Digit driver 2 | 25 | I | Keymatrix input O |
5 | O | Digit driver 3 | 24 | O | Segment driver DP |
6 | O | Digit driver 4 | 23 | O | Segment driver H |
7 | O | Digit driver 5 | 22 | O | Segment driver G |
8 | O | Digit driver 6 | 21 | O | Segment driver F |
9 | O | Digit driver 7 | 20 | O | Segment driver E |
10 | O | Digit driver 8 (MSD8) | 19 | O | Segment driver D |
11 | O | Digit driver 9 | 18 | O | Segment driver C |
12 | O | Digit driver 10 (MSD10) | 17 | O | Segment driver B |
13 | O | Digit driver 11 (OVER) | 16 | O | Segment driver A |
14 | V | Negative Voltage VDD | 15 | V | Negative Voltage VGG |
The Segment drivers A-H and the Decimal point are connected to a display in the pictured way. |
The keyboards of all calculators based on the TMS0102 family consist of a x/y-matrix connected to the digit driver outputs D1-D11 and the keymatrix inputs KN and KO. In the fixed-point output format mode the position of the decimal point is selcted with the KP input. The Constant/Chain switch is connected between D10-KQ.
[+=],[-=] Type |
[+],[-],[=] Type |
||||||||
KN | KO | KP | KQ | KN | KO | KP | KQ | ||
D1 | 1 | DP1 | D1 | 1 | + | DP1 | |||
D2 | 2 | * | DP2 | D2 | 2 | * | DP2 | ||
D3 | 3 | : | DP3 | D3 | 3 | : | DP3 | ||
D4 | 4 | DP4 | D4 | 4 | - | DP4 | |||
D5 | 5 | += | DP5 | D5 | 5 | DP5 | |||
D6 | 6 | -= | DP6 | D6 | 6 | DP6 | |||
D7 | 7 | +/- | DP7 | D7 | 7 | +/- | DP7 | ||
D8 | 8 | D8 | 8 | = | |||||
D9 | 9 | . | D9 | 9 | . | ||||
D10 | 0 | CE | DP0 | K | D10 | 0 | CE | DP0 | K |
D11 | C | D11 | C |
Calculators based on the TMS0102 use all kinds of displays. Texas Instruments introduced together with the calculator chip two pre-configured LED-modules (DIS40, DIS95) based on the TIL360 arrays ,the corresponding segment drivers (SN75491) and digit drivers (SN75492). Most designs make use of these parts.
If you have additions to the above datasheet please email: joerg@datamath.org.
© Joerg Woerner, February 02, 2001. No reprints
without written permission.