## Thursday, February 15, 2018

### Retro Review: Texas Instruments TI-60

Retro Review:  Texas Instruments TI-60

General Information

Company:  Texas Instruments
Type:  Programmable Scientific
Memory:  84 steps or 12 memory registers
Battery:  2 * Duracell MS76, Panasonic WL-14, Eveready 376 or 303, AG-13, SR44
Years:  1986 – 1991
Editions:  2:  1986 (Advanced Scientific), 1990 (Programmable Scientific)
Original Cost: \$50

Features

The TI-60 is a scientific keystroke programmable calculator, largely based off of the original TI-55 (1977).  The features of the TI-60:

Operating System:  AOS (Algebraic Operating System)  (like the TI-30Xa)
Programming:  Up to 56 program steps
Statistics:  Linear Regression
Conversions:  °F/°C, DMS/DD, in/cm, lb/kg, gal/L
Base Conversions:  Octal and Hexadecimal, has 2’s complement
Memory Registers: Up to 8, competed with both statistics and programming
Other Functions:  Percent Change, Absolute Value, Signum, Integer Part, Fractional Part
Integration
Shift Keys: 2nd, hyp, INV
Storage Arithmetic:  +, -, *, ÷, ^, roots, percent change

Percent Key (Δ%)

I think the percent works backwards than modern calculators.   Press the new value first, then [2nd] [ . ] ( Δ% ), then old value, [ = ].

Example:  Percent change from 32 to 56:  56 [2nd] [ . ] (Δ%) 32 [ = ] 75  (75% increase)

Combinations and Permutations

Like the TI-55 III, the arguments for combination and permutation functions take one argument in the form of nnn.rrr.

Example:

Combination where n = 25, r = 5 is entered as 25.005 [2nd] [ + ] (nCr)
(Result: 53,130)

Permutation where n = 25, r = 5 is entered as 25.005 [2nd] [ = ] (nPr)
(Result:  6,375,600)

Rectangular/Polar Conversion

[2nd] [x<>y] (P-R):  to Rectangular.  Input:  r [x<>y] θ [2nd] [x<>y] (P-R).  Result: y [x<>y] x.

[INV] [2nd] [x<>y] (P-R):  to Polar.   Input x [x<>y] y [INV] [2nd] [x<>y] (P-R).  Result:  θ [x<>y] r.

Linear Regression

The TI-60 has the parts labeled Intcp (y-intercept) and Slope. Running the statistics mode reduced the maximum number of steps to 20 until the statistics registers were cleared.

TI-60 vs TI-55 III

 TI-60 TI-55 III 84 maximum steps or 12 memory registers 56 maximum steps or 8 memory registers Clear programs outside of Learn mode Clear programs inside of Learn mode Each step you keyed is displayed in a PC(step #)  OP(key code #) format After each step, display is advanced to next available step, have to press BST to view what you just did, like the TI-58 series Base Mode:  Octal and Hexadecimal No base mode The RST (reset) instruction loops to Step 00 The RST (reset) instruction stops execution, directs program to Step 00

Verdict

I wish TI had implemented this keystroke system earlier.  I like the fact that the RST instruction allowed for loops.  I like that the user can see what was pressed after each step.

The TI-60 came at the tail end of the keystroke programmable calculators for Texas Instruments.  The keys are a pleasure a press, the contrast of the fonts is for the most part, excellent, except for the gray 1/x and 2nd functions on a gray background.

For the keystroke calculators from Texas Instruments, the TI-60 one of my favorite, second to the TI-58C.

Eddie

This blog is property of Edward Shore, 2018.

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