DATAMATH CALCULATOR MUSEUM

Texas Instruments TI Programmable 57

Date of introduction:	May 24, 1977	Display technology:	LED-stick
New price:	$79.95, £49.95 $40.00 (October, 1981)	Display size:	8 + 2
Size:	5.8" x 3.1" x 1.4" 148 x 78 x 36 mm³
Weight:	6.4 ounces, 180 grams	Serial No:	1246799
Batteries:	BP6, BP7	Date of manufacture:	wk 32 year 1977
AC-Adapter:	AC9131, AC9132	Origin of manufacture:	USA
Precision:	11	Integrated circuits:	TMC1501
Memories:	8
Program steps:	50	Courtesy of:	Joerg Woerner
Download leaflet:	(US: 2.2 MByte)	Download manual:	(DE: 13.1 MByte)

Introduced together with the TI-58 and TI-59 the TI-57 represented the low budget programmable calculator of that epoch and replaced the SR-56. Unbelievable that this powerful calculator made use of the one-chip approach of the SR-40 calculator.

A sales brochure of 1977 says: "The key to its value is a remarkable advance in integrated circuit technology - a single MOS/LSI chip with the equivalent capacity of 30,000 transistors". Well, today the guys of TI integrate millions and millions of transistor on one chip.

A novel step was the squeezing of key entries into program code, the time before the memory hold the key codes. This technique allowed up to 3 key entries (i.e. INV-2nd-sin) to be compressed into one program step. Sure that marketing sold a calculator with 50 memory places as a calculator with 150 program steps!

Please read this interesting comment from Anders Persson: "However, it was actually possible to pack up to four keystrokes in one step, not only three. An instruction like INV-2nd-Prd-4 would still fit in one step (code -39 4). Admittedly, not many instructions took four keystrokes - perhaps this is the only one...".

If you are interested in the calculating accuracy of scientific calculators don't miss the Calculator forensics.

Find a nice collection of program listings for the TI-57 on Laurent Bonnin's website.

Early in production (about wk 36 year 1977) TI changed the battery pack and the related connector and charger from the SR-51-II style to the TI-55 style. The battery packs are not compatible, don't use a BP6 with a AC9132 charger !

Simply by comparing the designation of the integrated circuits of the upper line "Majestic" calculators, you'll get the all members of this family:

• TMC1501    TI-57
• TMC1502    MBA
• TMC1503    TI-55

Later in production the metallized TI logo was replaced with an unmetallized. This gives in total 3 different US versions. View here the TI-57 w/o chrome. Finally we should add an early TI-57 assembled in Italy with different styling.

The TI-57 was sold under the label of Radio Shack as EC-4000.

The calculator was available till 1982.

The TI Programmable 57 is featured in the Texas Instruments Incorporated bulletins CL-274 and CL-283 dated 1977.

Find here an excerpt from the Texas Instruments Incorporated leaflet CL-199J dated 1981:

TI Programmable 57

The self-teaching programming system for student and professionals.

Eight multi-use memories provide addressable memory locations to store and recall data. Powerful program memory stores 50 fully merged steps (up to 150 key-strokes). Once a program is built, it can be executed repeatedly by supplying new sets of variables. Computer-like programming functions help solve repetitive problems quickly and accurately.
It’s also a powerful super slide rule calculator. AC adapter/charger and carrying case included.
Making Tracks into Programming. Takes you into the power and fun of programming right away, with step-by-step instructions and examples.

If you have additions to the above article please email: joerg@datamath.org.