Texas Instruments TI-59
Datasheet legend
Ab/c:
Fractions calculation
AC: Alternating current BaseN: Number base calculations Card: Magnetic card storage Cmem: Continuous memory Cond: Conditional execution Const: Scientific constants Cplx: Complex number arithmetic DC: Direct current Eqlib: Equation library Exp: Exponential/logarithmic functions Fin: Financial functions Grph: Graphing capability Hyp: Hyperbolic functions Ind: Indirect addressing Intg: Numerical integration Jump: Unconditional jump (GOTO) Lbl: Program labels LCD: Liquid Crystal Display LED: Light-Emitting Diode Li-ion: Lithium-ion rechargeable battery Lreg: Linear regression (2-variable statistics) mA: Milliamperes of current Mtrx: Matrix support NiCd: Nickel-Cadmium rechargeable battery NiMH: Nickel-metal-hydrite rechargeable battery Prnt: Printer RTC: Real-time clock Sdev: Standard deviation (1-variable statistics) Solv: Equation solver Subr: Subroutine call capability Symb: Symbolic computing Tape: Magnetic tape storage Trig: Trigonometric functions Units: Unit conversions VAC: Volts AC VDC: Volts DC |
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The TI-59 was a truly amazing calculator when it was introduced in 1977. A mind-boggling 960 program steps, 100 memories, a magnetic card reader, a rich variety of built-in functions, solid-state program ROM modules, and on top of that, an optional external printer/docking station made this beast a true geek dream machine. I remember going to sleep with a TI-59 brochure in my hands back when I was 15 or so... (well, I was also interested in girls, so I wasn't a hopeless case!)
Of course it was an unattainable dream; a price of several hundred dollars just for the calculator itself was too much even for most American kids of my age. However, a few years later, I did in fact come in close contact with this machine, when I was writing flight simulation software for the Hungarian air traffic management authority.
As it turns out, I still have a few of those old magnetic cards in my possession. Having recently obtained a TI-59 that works really well, I was amazed to find out that the cards are actually readable after almost 20 years. It took a few tries but I was able to load, and print, several of my old programs, including the one calculating take-off distances for passenger jets under various load, runway, and engine conditions. It was amazing to see those old programs come to life, and follow the take-off of a TU-154 again as rows of numbers representing distance, speed, and altitude began to appear in printout.
Except for a richer instruction set and some keycode merging (not nearly as extensive though as the merging on HP calculators) the TI-59 has a very similar programming model to that of the SR-52. Of course those extra features made a world of a difference; for instance, the TI-59 was the first pocket calculator that knew about letters, not just numbers. Although its display used traditional 7-segment digits, the TI-59 was capable of printing arbitrary text on the PC-100 printer.
Apparently, the TI-59's card reader suffers from the same disease as Hewlett-Packard's card readers in their early calculators: the rubber of its pinch wheel disintegrates over time, turning into a yucky, gummy deposit. Because there's more friction along the card path than in HP calculators, it appears this calculator is more sensitive to the exact geometry of the wheel. So although I have made several attempts, I have yet to claim that I have repaired a TI-59's card reader to a degree that I'd call satisfactory. Fortunately, several of my TI-59s still have their wheels intact.
The TI-59 had two smaller cousins. The TI-58 had about half the memory and no card reader, which meant that programs were lost when the calculator was powered down. The TI-58C was a TI-58 with continuous memory.
All three calculators in this family have undocumented features. Most notable among these is the infamous HIR instruction, which allows the programmer to access a variety of hidden ("hierarchy") registers.
Solid-state modules really added to the power of these calculators. With these modules, it is actually possible to create a complex implementation of the Gamma function for the TI-59. The version shown here uses 309 program steps, so it fits on the two sides of a single magnetic card.
The program calculates the complex Gamma function for any complex argument, entered using the x-t key. For instance, to calculate the Gamma function of 1+3i, you'd type 1 x-t 3 A. After a somewhat lengthy computation, the calculator will display the real part of the result (0.019292759); the imaginary part (.0338960105) can be retrieved using x-t again. To calculate the Gamma function of a real number such as 5, type 5 x-t 0 A.
Note that this program requires the presence of the Master Library 1 module in the calculator's Solid State Library slot. If the module is not present, or if another module is inserted, the program will not function correctly.
000 76 LBL 001 11 A 002 42 STO 003 04 04 004 32 x-t 005 42 STO 006 03 03 007 01 1 008 42 STO 009 01 01 010 00 0 011 42 STO 012 02 02 013 29 CP 014 76 LBL 015 32 x-t 016 43 RCL 017 03 03 018 77 x>=t 019 61 GTO 020 36 PGM 021 04 04 022 13 C 023 01 1 024 44 SUM 025 03 03 026 61 GTO 027 32 x-t 028 76 LBL 029 61 GTO 030 43 RCL 031 01 01 032 42 STO 033 05 05 034 43 RCL 035 02 02 036 42 STO 037 06 06 038 02 2 039 65 × 040 89 π 041 95 = 042 34 √ 043 42 STO 044 01 01 045 00 0 046 42 STO 047 02 02 048 36 PGM 049 04 04 050 13 C 051 93 . 052 08 8 053 06 6 054 07 7 055 06 6 056 00 0 057 04 4 058 03 3 059 04 4 060 02 2 061 04 4 062 85 + 063 08 8 064 03 3 065 95 = 066 44 SUM 067 01 01 068 36 PGM 069 04 04 070 13 C 071 93 . 072 09 9 073 02 2 074 06 6 075 04 4 076 09 9 077 04 4 078 07 7 079 09 9 080 85 + 081 01 1 082 01 1 083 06 6 084 08 8 085 95 = 086 44 SUM 087 01 01 088 36 PGM 089 04 04 090 13 C 091 93 . 092 02 2 093 04 4 094 05 5 095 02 2 096 09 9 097 07 7 098 00 0 099 05 5 100 85 + 101 08 8 102 06 6 103 08 8 104 07 7 105 95 = 106 44 SUM 107 01 01 108 36 PGM 109 04 04 110 13 C 111 93 . 112 02 2 113 09 9 114 05 5 115 01 1 116 04 4 117 07 7 118 07 7 119 85 + 120 03 3 121 06 6 122 03 3 123 00 0 124 08 8 125 95 = 126 44 SUM 127 01 01 128 36 PGM 129 04 04 130 13 C 131 93 . 132 06 6 133 02 2 134 07 7 135 08 8 136 09 9 137 05 5 138 02 2 139 85 + 140 08 8 141 00 0 142 09 9 143 01 1 144 06 6 145 85 + 146 53 ( 147 93 . 148 06 6 149 03 3 150 03 3 151 01 1 152 05 5 153 03 3 154 85 + 155 07 7 156 05 5 157 01 1 158 02 2 159 02 2 160 54 ) 161 48 EXC 162 01 01 163 95 = 164 42 STO 165 07 07 166 00 0 167 48 EXC 168 02 02 169 42 STO 170 08 08 171 36 PGM 172 04 04 173 18 C' 174 43 RCL 175 07 07 176 44 SUM 177 01 01 178 43 RCL 179 08 08 180 44 SUM 181 02 02 182 01 1 183 44 SUM 184 03 03 185 94 +/- 186 49 PRD 187 04 04 188 36 PGM 189 04 04 190 18 C' 191 01 1 192 44 SUM 193 03 03 194 94 +/- 195 49 PRD 196 04 04 197 36 PGM 198 04 04 199 18 C' 200 01 1 201 44 SUM 202 03 03 203 94 +/- 204 49 PRD 205 04 04 206 36 PGM 207 04 04 208 18 C' 209 01 1 210 44 SUM 211 03 03 212 94 +/- 213 49 PRD 214 04 04 215 36 PGM 216 04 04 217 18 C' 218 01 1 219 44 SUM 220 03 03 221 94 +/- 222 49 PRD 223 04 04 224 36 PGM 225 04 04 226 18 C' 227 01 1 228 44 SUM 229 03 03 230 94 +/- 231 49 PRD 232 04 04 233 36 PGM 234 04 04 235 18 C' 236 36 PGM 237 05 05 238 16 A' 239 43 RCL 240 03 03 241 75 - 242 93 . 243 05 5 244 95 = 245 48 EXC 246 01 01 247 42 STO 248 07 07 249 43 RCL 250 04 04 251 94 +/- 252 42 STO 253 04 04 254 48 EXC 255 02 02 256 42 STO 257 08 08 258 36 PGM 259 05 05 260 16 A' 261 05 5 262 93 . 263 05 5 264 22 INV 265 44 SUM 266 03 03 267 36 PGM 268 04 04 269 13 C 270 43 RCL 271 08 08 272 75 - 273 43 RCL 274 04 04 275 95 = 276 44 SUM 277 02 02 278 43 RCL 279 07 07 280 75 - 281 43 RCL 282 03 03 283 75 - 284 05 5 285 95 = 286 44 SUM 287 01 01 288 36 PGM 289 05 05 290 17 B' 291 43 RCL 292 05 05 293 42 STO 294 03 03 295 43 RCL 296 06 06 297 42 STO 298 04 04 299 36 PGM 300 04 04 301 18 C' 302 43 RCL 303 02 02 304 32 x-t 305 43 RCL 306 01 01 307 92 RTN
Do you want to test drive a TI-59 yourself without spending an arm and a leg to buy one in questionable condition on eBay? I recently came across a wonderful TI-59 emulator on the Web: http://www.n3times.com/vertigo/ is the address. The emulator isn't 100% complete yet, but it's pretty darn close and it's pretty darn good, too!