The TI-59 is an early
programmable calculator
Programmable calculators are calculators that can automatically carry out a sequence of operations under control of a stored program. Most are Turing complete, and, as such, are theoretically general-purpose computers. However, their user inter ...
, that was manufactured by
Texas Instruments
Texas Instruments Incorporated (TI) is an American technology company headquartered in Dallas, Texas, that designs and manufactures semiconductors and various integrated circuits, which it sells to electronics designers and manufacturers globa ...
from 1977. It is the successor to the TI SR-52, quadrupling the number of "program steps" of storage, and adding "ROM Program Modules" (an insertable ROM chip, capable of holding 5000 program steps). Just like the SR-52, it has a magnetic card reader for external storage. One quarter of the memory is stored on each side of one card.
The TI-58 (May 1977), and later TI-58C (1979), are cut-down versions of the TI-59, lacking the magnetic card reader and having half the memory, but otherwise identical. Although the TI-58C uses a different chip than the TI-58, the technical data remain identical. The "C" in a TI (or Hewlett-Packard) model name indicates that the calculator has a ''constant'' memory (or
continuous memory The term continuous memory was coined by Hewlett-Packard (HP) to describe a unique feature of certain HP calculators whereby the calculator could internally sustain most, or in later models - all, of the contents of user memory (via battery-backed C ...
, respectively) allowing retention of programs and data when turned off.
These calculators use a parenthesized infix calculation system called "
Algebraic Operating System
There are various ways in which calculators interpret keystrokes. These can be categorized into two main types:
* On a single-step or immediate-execution calculator, the user presses a key for each operation, calculating all the intermediate resu ...
" (AOS), where, compared to the postfix
RPN system used by other scientific calculators (such as HP), the operator enters calculations just as they are written on paper, using up to nine levels of parenthesis.
The calculator can be powered from an external
adapter
An adapter or adaptor is a device that converts attributes of one electrical device or system to those of an otherwise incompatible device or system. Some modify power or signal attributes, while others merely adapt the physical form of one c ...
or from internal
NiCd rechargeable battery pack (although the battery has to remain present when using the external AC adapter to avoid damage to the calculator circuitry).
Display
The red LED display shows 10 decimal digits of precision.
Programming
Programming simple problems with the TI-59 or TI-58 is a very straightforward process. In programming mode, the TI-59 simply records key presses. Alphabetical keys provide easy access to up to ten entry points.
It is also possible to activate any of the programs in the pre-programmed memory module, and run one like any user-written program. Programs written by the user can also use programs in the module as subroutines. The module's programs run directly from
ROM
Rom, or ROM may refer to:
Biomechanics and medicine
* Risk of mortality, a medical classification to estimate the likelihood of death for a patient
* Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac
* ...
, so they leave the calculator's memory free for the user.
However, exploiting the computer-like capabilities of the TI-59 is a different matter. Although the TI-59 is
Turing-complete
In computability theory, a system of data-manipulation rules (such as a computer's instruction set, a programming language, or a cellular automaton) is said to be Turing-complete or computationally universal if it can be used to simulate any ...
, supporting straight-line programming, conditions, loops, and indirect access to memory registers, and although it supports limited alphanumeric output on the printer only, writing sophisticated routines is essentially a matter of planning machine language and using a coding pad.
A large degree of sharing occurred in the TI-59 and TI-58 community. At least one
game, ''Darth Vader's Force Battle'', appeared as a
type-in program
A type-in program or type-in listing was computer source code printed in a home computer magazine or book. It was meant to be entered via the keyboard by the reader and then saved to cassette tape or floppy disk. The result was a usable game, ...
.
Programming example
Here is a sample program that computes the factorial of an integer number from 2 to 69. For 5!, if "5 A" is pressed, it gives the result, 120. Unlike the SR-52, the TI-58 and TI-59 do not have the factorial function built-in, but do support it through the software module which was delivered with the calculator.
Op-code Comment
LBL A ''You'll call the program with the A key''
STO 01 ''stores the value in register 1''
1 ''starts with 1''
LBL B ''label for the loop''
* ''multiply''
RCL 01 ''by n''
DSZ 1 B ''decrements n and back to B until n=0''
= ''end of loop, the machine has''
''calculated 1*n*(n-1)*...2*1=n!''
INV SBR ''end of procedure''
Here is the same program written for TI Compiler:
[TI User, programs on line, TI Compiler page.]
/ref>
#reg 01 counter
#label A factorial
LBL factorial
STO counter
1
FOR counter
* @counter
LOOP
=
RTN
#end
Memory
In comparison to its contemporary main competitor, Hewlett-Packard HP-67
The HP-67 is a magnetic card-programmable handheld calculator, introduced by Hewlett-Packard in 1976 at an MSRP of $450. A desktop version with built-in thermal printer was sold as the HP-97 at a price of $750.
Marketed as improved successor ...
, the TI-59 has about twice the memory
Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembered ...
. The partition between program steps and memories is adjustable in increments of 80 program steps/10 memories, and as many as 960 program steps (with zero memories) or as many as 100 memories (with 160 program steps) can be configured. The TI-59 was the first programmable pocket calculator where the manufacturer provided a system for sharing memory between data registers and program storage. The memory is only about twice as large as in the SR-52, but more flexible, and thus the possible number of program steps was four times as high. Contents of this memory are lost when the calculator is turned off.
The TI-58 has half the memory of the TI-59 and supports up to 480 program steps or 60 memories. It competed with the HP-34C
The HP-34C continuous memory calculator was an advanced scientific programmable calculator of the HP 30 series. It was produced between 1979 (cost US$150) and 1983 (cost US$100).
Features Root-finding and integration
Significant to the HP- ...
.
The TI-58 and TI-59 calculators have variable-length instructions. Some keypresses are merged into one programming step, so that instructions from one to eleven keypresses are stored in one to six programming steps. The HP-67
The HP-67 is a magnetic card-programmable handheld calculator, introduced by Hewlett-Packard in 1976 at an MSRP of $450. A desktop version with built-in thermal printer was sold as the HP-97 at a price of $750.
Marketed as improved successor ...
always stores one instruction in one programming step, which is efficient for some frequently used instructions but also limits the number of possible instructions.
Magnetic card reader
The TI-59 can store programs and data on small magnetic cards when the calculator is turned off and quickly reloaded when needed. Click below for a video of the card reader in action.
The video also shows the dual use of the magnetic card as a program documentation menu. Notes can be printed or handwritten by the programmer on the top side of the magnetic card. Once read by the cardreader, the card can then be stored, as shown, in a slot between the top of the keyboard and the display, thus providing a notation indicating both the name of the program currently loaded and the purpose of each of the five label buttons A-E and their secondary functions A'-E' within the loaded program.
The TI-58 does not have a magnetic card reader.
Solid State Software Library
The TI-59 and TI-58 were the first hand-held calculators to utilize removable ROM
Rom, or ROM may refer to:
Biomechanics and medicine
* Risk of mortality, a medical classification to estimate the likelihood of death for a patient
* Rupture of membranes, a term used during pregnancy to describe a rupture of the amniotic sac
* ...
program modules. The Master Library Module ROM was included with the TI-59 and TI-58, and contains several useful pre-programmed routines and even a game. Additional modules - for such applications as real estate
Real estate is property consisting of land and the buildings on it, along with its natural resources such as crops, minerals or water; immovable property of this nature; an interest vested in this (also) an item of real property, (more general ...
, investment, statistics, surveying and aviation
Aviation includes the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes fixed-wing and rotary-wing types, morphable wings, wing-less lifting bodies, as well as lighter-than-air craft such as hot a ...
- were sold separately.
The programs in the modules used the user-defined keys heavily. To make the programs easier to use, plastic cards with the same size as the magnetic cards, but just printed to label the user-defined keys, can be inserted in the slot between the display and the keyboard to label the user-defined keys.
Printer
Also available for the TI-59 and TI-58 was a thermal printer
Thermal printing (or direct thermal printing) is a digital printing process which produces a printed image by passing paper with a thermochromic coating, commonly known as thermal paper, over a print head consisting of tiny electrically heated ...
(the PC-100A, B, and C models); the calculator was mounted on top of the printer and locked in place with a key.
The calculator can be programmed to request input from the user, and output results of calculations to the printer. Alphanumeric text (64 characters total, including space, 0-9, A-Z and 25 punctuation and mathematical symbols) can be output as well as numbers. A limited ability to plot graphs is provided. The printer is also valuable for program development because it can produce a hard copy of the calculator's program including the alphanumeric mnemonics instead of just the numeric codes normally visible on the display, as well as a dump of the data registers, a trace of the program's execution and other information about the program.
In the early model PC-100A, a switch inside the battery charger compartment allows use with the earlier SR-52 and SR-56 calculators as well as the TI-58/59 series. In addition, it also works with non-programmable TI machines of the era such as the SR-50A. (Remove the battery pack of a TI calculator and look for the row of printer interface pads on the circuit board below the battery terminals.)
References
External links
TI-59 homepage
maintained by Dejan Ristanovic
TI-59 library
maintained by Viktor Toth
o
DataMath.org
TI-59
TI-58
TI-58C
o
MyCalcDB
(database about 1970s and 1980s pocket calculators)
Short article published on the TI-59's 30th birthday
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*
*
TI-59, TI-58C, TI-58 German documentation
*
ti58c.phweb.me, TI-58/TI-58C/TI-59 Emulator on Windows
{{DEFAULTSORT:TI-59 TI-58
Texas Instruments programmable calculators
Articles containing video clips