See a video at: https://youtu.be/l01LcFuFtyg
Welcome to SPARK35 - a HP-35 emulator on Arduino
(Digispark on QYF-TM1638 platform)
Version 1.0 ... (c) 2022 by deetee/zooxo
This software is covered by the 3-clause BSD license.
See also: https://github.com/zooxo/spark35
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PREAMBLE
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In January 1972, Hewlett-Packard introduced the HP-35 the first scientific
calculator and revolutionized the way to calculate. Peter Monta,
Jacques Laporte and Pietro de Luca reverse-reengineered the HP-35 to use the
HP-35-ROM on AVR microcontroller.
SPARK35 uses this emulator to run the HP-35 on a Digispark (ATTINY85) and the
QYF-TM1638 development board. Despite the small flash memory (6012 bytes)
SPARK35 adds some extra funktions like hyperbolics, present value, complex
conversions, gamma, standard normal distribution and quadratic equation.
Enjoy!
deetee
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KEYBOARD LAYOUT
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F(G)[OFF] 7(1/X)[SIN] 8(SQRT)[->P] 9(/)[->R]
EEX(SWAP)[] 4(X^Y)[COS] 5(LOG)[PV] 6(*)[ND]
CHS(ROT)[] 1(EXP)[TAN] 2(LN)[LN!] 3(-)[QE]
CLX(CLR)[LIT+] 0(STO)[ARC] .(RCL)[HYP] ENTER(+)[PI]
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OPERATIONS
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. 0 1 2 3 4 5 6 7 8 9 ... Number keys
ENTER CHS EEX CLX CLR SWAP ROT STO RCL ... Management keys
- * + / 1/X SQRT X^Y LOG LN EXP PI ... Basic mathematical operations
ARC SIN COS TAN ... Trigonometric functions
HYP ... Demand hyperbolic function
(7|4|1 -> SINH|COSH|TANH, 8|5|2 -> ASINH|ACOSH|ATANH)
->P ->R ... Complex conversion (polar vs. rectangular)
PV ... Present value of annuity
(ie i=0.08 rate and n=5 periods equals a PV=3.99)
ND ... Standard normal distribution (PDF/CDF)
LN! ... ln(GAMMA)
QE ... Quadratic equation
(enter -5 and 6 to find the roots of y=xx-5x+6 -> 3, 2)
F G ... Function keys
OFF ... Switch off display
LIT+ ... Raise brightness of display (7 levels)
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HARDWARE
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VCC=5V | 8.8.8.8.8.8.8.8. |
--------- GND-|GND |
VCC-| VCC P1 |----------|DIO * * * |
| P2 |----------|CLK * * * |
GND-| GND P3 |----------|STB * * * |
---------- VCC-|VCC * * * |
DIGISPARK ------------------
QYF-TM1638
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HP-35 DESIGN
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| |
| -1.234567890-12 | Key codes
|_________________________| (default: 0xff)
| |
| X^Y log ln e^X CLR | - 6 - 4 3 2 - 0
| SQRT arc sin cos tan | - 46 - 44 43 42 - 40
| 1/X X><Y ROT STO RCL | - 14 - 12 11 10 - 8
| E-N-T-E-R CHS EEX CLX | - 62 - - 59 58 - 56
| - 7 8 9 | - 54 - 52 51 50 - -
| + 4 5 6 | - 22 - 20 19 18 - -
| * 1 2 3 | - 30 - 28 27 26 - -
| / 0 . PI | - 38 - 36 35 34 - -
|_________________________|