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Comparison of HP graphing calculators
Class of hand-held calculator

A graphing calculator is a class of hand-held calculator that is capable of plotting graphs and solving complex functions. While there are several companies that manufacture models of graphing calculators, Hewlett-Packard is a major manufacturer.

The following table compares general and technical information for Hewlett-Packard graphing calculators:

ModelProcessorMemoryDisplayInput methodStackProgramming languagesComputer algebra systemCharacter setSoundConnectivityPower supplyRelease yearPredecessorsSuccessors
HP Prime G2 (2AP18AA)528 MHz NXP i.MX 6ULL MCIMX6Y2 (Cortex A7 core, ARMv7 architecture)256 MB RAM, 512 MB flash320×240 pixel 16-bit color multi-touch TFT LCD with backlightAlgebraic, Entry RPNFixed (128 level)PPLXcas/Giac-basedUnicodeNoUSB (Micro-AB) USB-OTGUSB-rechargeable 3.7 V/2000 mAh/7.4 Wh Li-Ion, USB2018–presentHP Prime G1None
HP Prime G1 (NW280AA, G8X92AA)400 MHz Samsung S3C2416XH-40 (ARM926EJ core, ARMv5 architecture)32 MB RAM, 256 MB flash320×240 pixel 16-bit color multi-touch TFT LCD with backlightAlgebraic, Entry RPNFixed (128 level)PPLXcas/Giac-basedUnicodeNoUSB (Micro-AB) (USB-OTG only with G8X92AA model)USB-rechargeable 3.7 V/1500 mAh/5.55 Wh Li-Ion (compatible: Samsung Galaxy S3 2200 mAh), USB2013–2017HP 39gII, (HP 50g)HP Prime G2
HP 50g blue (NW240AA)75 MHz (203 MHz) Samsung S3C2410A (ARM920T core, ARMv4T architecture)512 KB RAM, 2 MB flash, expandable via 2 GB SD card131×80 pixel monochrome LCDEntry RPN, AlgebraicDynamicRPL, Algebraic RPLErable-based8-bit RPL character set (with euro sign)BuzzerUSB (Mini-B), IrDA, 1×4-pin 3.3 V TTL serial (RS-232 via active converter)4×1.5 V (6 V) AAA, 1×3 V CR2032, USB2009–2012HP 50g (hp 49g+)(HP Prime)
HP 50g black (F2229A)75 MHz (203 MHz) Samsung S3C2410A (ARM920T core, ARMv4T architecture)512 KB RAM, 2 MB flash, expandable via 2 GB SD card131×80 pixel monochrome LCDEntry RPN, AlgebraicDynamicRPL, Algebraic RPLErable-based8-bit RPL character set (with euro sign)BuzzerUSB (Mini-B), IrDA, 1×4-pin 3.3 V TTL serial (RS-232 via active converter)4×1.5 V (6 V) AAA, 1×3 V CR2032, USB2006–2015hp 49g+(HP Prime)
hp 49g+ (F2228A)75 MHz (203 MHz) Samsung S3C2410X01 (ARM920T core, ARMv4T architecture)512 KB RAM, 2 MB flash, expandable via 2 GB SD card131×80 pixel monochrome LCDEntry RPN, AlgebraicDynamicRPL, Algebraic RPLErable-based8-bit RPL character set (with euro sign)BuzzerUSB (Mini-B), IrDA3×1.5 V (4.5 V) AAA, 1×3 V CR20322003–2006HP 49GHP 50g
HP 48gII (F2226A)48 MHz (203 MHz) Samsung S3C2410X01 (ARM920T core, ARMv4T architecture)128 KB RAM (256 KB RAM - 2007 model only), not flashable131×64 pixel monochrome LCDEntry RPN, AlgebraicDynamicRPL, Algebraic RPLErable-based8-bit RPL character set (with euro sign)Buzzer(USB (Mini-B) - 2007 model only), IrDA, 1×4-pin 3.3 V TTL serial (RS-232 via active converter)3×1.5 V (4.5 V) AAA (4×1.5 V (6 V) AAA - 2007 model only), 1×3 V CR2032, USB (2007 model only)2003HP 48G+HP 49g+
HP 49G (F1633A, F1896A)4 MHz Yorke (Saturn 1LT8 core)512 KB RAM, 2 MB flash131×64 pixel monochrome LCDEntry RPN, AlgebraicDynamicRPL, Algebraic RPLErable-based8-bit RPL character set (with euro sign)Buzzer2×5-pin RS-2323×1.5 V (4.5 V) AAA1999–2003HP 48GX, HP 48G+hp 49g+
HP 48G+ (F1630A, F1894A)4 MHz Yorke (Saturn 1LT8 core)128 KB RAM, not flashable131×64 pixel monochrome LCDEntry RPNDynamicRPLRudimentary8-bit RPL character setBuzzer1×4-pin RS-232, HP SIR3×1.5 V (4.5 V) AAA1998–2003HP 48GHP 49G
HP 48G3.68-4 MHz Yorke (Saturn 1LT8 core)32 KB RAM, not flashable131×64 pixel monochrome LCDEntry RPNDynamicRPLRudimentary8-bit RPL character setBuzzer1×4-pin RS-232, HP SIR3×1.5 V (4.5 V) AAA1993–2003HP 48SHP 48G+, HP 49G
HP 48GX (F1895A)4 MHz Yorke (Saturn 1LT8 core)128 KB RAM, expandable via 128 KB and 4 MB max. card slots, not flashable131×64 pixel monochrome LCDEntry RPNDynamicRPLRudimentary8-bit RPL character setBuzzer1×4-pin RS-232, HP SIR3×1.5 V (4.5 V) AAA1993–2003HP 48SXHP 49G
HP 48S2 MHz Clarke (Saturn 1LT8 core)32 KB RAM, not flashable131×64 pixel monochrome LCDEntry RPNDynamicRPLRudimentary8-bit RPL character setBuzzer1×4-pin RS-232, HP SIR3×1.5 V (4.5 V) AAA1991–1993HP-28SHP 48G
HP 48SX2 MHz Clarke (Saturn 1LT8 core)32 KB RAM, expandable via 2 card slots of 128 KB RAM/ROM each, not flashable131×64 pixel monochrome LCDEntry RPNDynamicRPLRudimentary8-bit RPL character setBuzzer1×4-pin RS-232, HP SIR3×1.5 V (4.5 V) AAA1990–1993HP-28SHP 48GX
HP 39gII (NW249AA)80 MHz Freescale (formerly SigmaTel) STMP3770 (ARM926EJ-S core)256 KB RAM (ca. 240 KB available to user), 128 MB flash (80–105 MB available to user)256×128 pixel monochrome gray-scale LCDAlgebraicDynamicHP Basic-variant or PPL-predecessor?NoUnicodeNoUSB-OTG (Micro-AB)1–4×1.5 V (1.5 V) AAA, USB2011HP 39gsHP Prime
HP 40gs (F2225A)75 MHz Samsung S3C2410A (ARM920T core, ARMv4T architecture)256 KB RAM, 2 MB flash131×64 pixel monochrome LCDAlgebraicDynamicHP BasicErable-based8-bit RPL character set (with −1 and euro sign)BuzzerUSB (Mini-B), 1×4-pin 3.3 V TTL serial (RS-232 via active converter)4×1.5 V (6 V) AAA, 1×3 V CR2032, USB2006–2011HP 40GHP 39gII, HP Prime
HP 39gs (F2223A)75 MHz Samsung S3C2410A (ARM920T core, ARMv4T architecture)256 KB RAM, 1 MB flash131×64 pixel monochrome LCDAlgebraicDynamicHP BasicNo8-bit RPL character set (with −1 and euro sign)BuzzerUSB (Mini-B), IrDA, 1×4-pin 3.3 V TTL serial (RS-232 via active converter)4×1.5 V (6 V) AAA, 1×3 V CR2032, USB2006–2011hp 39g+HP 40gs, HP 39gII
hp 39g+ (F2224A)75 MHz Samsung S3C2410X (ARM920T core, ARMv4T architecture)256 KB RAM, 1 MB flash131×64 pixel monochrome LCDAlgebraicDynamicHP BasicNo8-bit RPL character set (with −1 and euro sign)BuzzerUSB (Mini-B), IrDA3×1.5 V (4.5 V) AAA, 1×3 V CR20322003–2006HP 39GHP 39gs
HP 40G (F1907A)4 MHz Yorke (Saturn 1LT8 core)256 KB RAM, not flashable131×64 pixel monochrome LCDAlgebraicDynamicHP BasicErable-based8-bit RPL character set (with −1 and euro sign)Buzzer2×5-pin RS-2323×1.5 V (4.5 V) AAA2000–2003HP 38GHP 40gs
HP 39G (F1906A)4 MHz Yorke (Saturn 1LT8 core)256 KB RAM, not flashable131×64 pixel monochrome LCDAlgebraicDynamicHP BasicNo8-bit RPL character set (with −1 and euro sign)BuzzerIrDA, 2×5-pin RS-2323×1.5 V (4.5 V) AAA2000–2003HP 38Ghp 39g+
HP 38G (F1200A, F1892A)4 MHz Yorke (Saturn 1LT8 core)32 KB RAM, not flashable4-line (131×64 pixel) monochrome LCDAlgebraicDynamicHP BasicNo8-bit RPL character setBuzzerHP SIR, 2×5-pin RS-2323×1.5 V (4.5 V) AAA1995NoneHP 39G, HP 40G
HP-28S1 MHz Lewis (Saturn 1LR2 core)32 KB RAM, not flashable4-line (137×32 pixel) monochrome LCDEntry RPNDynamicRPLRudimentary8-bit HP Roman 8 variantBuzzerHP SIR3×1.5 V (4.5 V) N1988–1992HP-28CHP 48 series
HP-28C640 kHz Saturn (Saturn 1LK7 core)2 KB RAM, 1709? bytes RAM available for user, not flashable4-line (137×32 pixel) monochrome LCDEntry RPNDynamicRPLRudimentary8-bit HP Roman 8 variantBuzzerHP SIR3×1.5 V (4.5 V) N1987–1988HP-41CHP-28S
HP-42S1 MHz Lewis (Saturn core)8 KB RAM (extensible to 32 KB), 7200? (or 31553) bytes RAM available for user, not flashable2-line (131×16 pixel) monochrome LCDClassical RPNFixed (4 level)Keystroke programmable, fully merged (FOCAL variant)None8-bit proprietaryBuzzerHP SIR3×1.5 V (4.5 V) LR441987–1995HP-41C, (HP-15C)HP-28S
HP 9gSunplus SPLB30A (aka Generalplus GPLB30A)712? bytes RAM available for user, not flashable35×23 pixel, 1-line 5-digit 5×7 dot matrix, 1-line 10+3-digit 7-segment monochrome LCDAlgebraic?Limited, 10 programmable "expression registers" that can reference other functions, registers, and memoryNo?NoNone1×3 V CR20252003NoneNone
ModelProcessorMemoryDisplayInput methodStackProgramming languagesComputer algebra systemCharacter setSoundConnectivityPower supplyRelease yearPredecessorsSuccessors

See also

References

  1. "Hewlett-Packard HP 50g scientific calculator". ARM. Archived from the original on 2015-03-09. Retrieved 2015-03-13. https://archive.today/20150309154238/http://www.arm.com/markets/embedded/hewlett-packard-hp-50g-scientific-calculator.php ↩

  2. HP 50g / 49g+ / 48gII graphing calculator advanced user’s reference manual (AUR) (2 ed.). Hewlett-Packard. 2009-07-14 [2005]. pp. J-1, J-2. HP F2228-90010. Archived from the original on 2018-09-28. Retrieved 2015-10-10. [1]Searchable PDF http://www.hpcalc.org/details.php?id=7141 ↩

  3. Prange, James M. (2006-11-02). "Re: Those solid block characters in the characters menu". HP Forum Archive 16. The Museum of HP Calculators (MoHPC). Archived from the original on 2016-08-02. Retrieved 2016-08-02. http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv016.cgi?read=101928 ↩

  4. Rautenberg, Wolfgang (2004-05-09). "IOMAN - A small but powerful I/O manager for the HP49G/HP49g+". 5.2004. Archived from the original on 2016-08-02. Retrieved 2016-08-02. [2] /wiki/Wolfgang_Rautenberg ↩

  5. Kuperus, Klaas (2015-03-04). "HP 50g: End of an era". forum.hp-prime.de. Moravia. Archived from the original on 2015-04-02. https://web.archive.org/web/20150402112232/http://forum.hp-prime.de/discussion/787/hp-50g-end-of-an-era ↩

  6. Kuperus, Klaas (2015-03-06). "HP 50g not so good news?". HP Museum. Moravia. Archived from the original on 2018-07-08. Retrieved 2016-01-01. http://www.hpmuseum.org/forum/thread-3265-post-29694.html#pid29694 ↩

  7. Wessman, Timothy "Tim" James (2015-12-26). "Windows 10 won't allow HP 50g USB drivers to be installed". HP Museum. Archived from the original on 2018-07-08. Retrieved 2016-01-01. http://www.hpmuseum.org/forum/thread-5386-post-48114.html#pid48114 ↩

  8. "Hewlett-Packard HP 50g scientific calculator". ARM. Archived from the original on 2015-03-09. Retrieved 2015-03-13. https://archive.today/20150309154238/http://www.arm.com/markets/embedded/hewlett-packard-hp-50g-scientific-calculator.php ↩

  9. HP 50g / 49g+ / 48gII graphing calculator advanced user’s reference manual (AUR) (2 ed.). Hewlett-Packard. 2009-07-14 [2005]. pp. J-1, J-2. HP F2228-90010. Archived from the original on 2018-09-28. Retrieved 2015-10-10. [1]Searchable PDF http://www.hpcalc.org/details.php?id=7141 ↩

  10. Prange, James M. (2006-11-02). "Re: Those solid block characters in the characters menu". HP Forum Archive 16. The Museum of HP Calculators (MoHPC). Archived from the original on 2016-08-02. Retrieved 2016-08-02. http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv016.cgi?read=101928 ↩

  11. Rautenberg, Wolfgang (2004-05-09). "IOMAN - A small but powerful I/O manager for the HP49G/HP49g+". 5.2004. Archived from the original on 2016-08-02. Retrieved 2016-08-02. [2] /wiki/Wolfgang_Rautenberg ↩

  12. Kuperus, Klaas (2015-03-04). "HP 50g: End of an era". forum.hp-prime.de. Moravia. Archived from the original on 2015-04-02. https://web.archive.org/web/20150402112232/http://forum.hp-prime.de/discussion/787/hp-50g-end-of-an-era ↩

  13. Kuperus, Klaas (2015-03-06). "HP 50g not so good news?". HP Museum. Moravia. Archived from the original on 2018-07-08. Retrieved 2016-01-01. http://www.hpmuseum.org/forum/thread-3265-post-29694.html#pid29694 ↩

  14. Wessman, Timothy "Tim" James (2015-12-26). "Windows 10 won't allow HP 50g USB drivers to be installed". HP Museum. Archived from the original on 2018-07-08. Retrieved 2016-01-01. http://www.hpmuseum.org/forum/thread-5386-post-48114.html#pid48114 ↩

  15. HP 50g / 49g+ / 48gII graphing calculator advanced user’s reference manual (AUR) (2 ed.). Hewlett-Packard. 2009-07-14 [2005]. pp. J-1, J-2. HP F2228-90010. Archived from the original on 2018-09-28. Retrieved 2015-10-10. [1]Searchable PDF http://www.hpcalc.org/details.php?id=7141 ↩

  16. Prange, James M. (2006-11-02). "Re: Those solid block characters in the characters menu". HP Forum Archive 16. The Museum of HP Calculators (MoHPC). Archived from the original on 2016-08-02. Retrieved 2016-08-02. http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv016.cgi?read=101928 ↩

  17. Rautenberg, Wolfgang (2004-05-09). "IOMAN - A small but powerful I/O manager for the HP49G/HP49g+". 5.2004. Archived from the original on 2016-08-02. Retrieved 2016-08-02. [2] /wiki/Wolfgang_Rautenberg ↩

  18. Prange, James M. (2006-11-02). "Re: Those solid block characters in the characters menu". HP Forum Archive 16. The Museum of HP Calculators (MoHPC). Archived from the original on 2016-08-02. Retrieved 2016-08-02. http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv016.cgi?read=101928 ↩

  19. Rautenberg, Wolfgang (2004-05-09). "IOMAN - A small but powerful I/O manager for the HP49G/HP49g+". 5.2004. Archived from the original on 2016-08-02. Retrieved 2016-08-02. [2] /wiki/Wolfgang_Rautenberg ↩

  20. Prange, James M. (2006-11-02). "Re: Those solid block characters in the characters menu". HP Forum Archive 16. The Museum of HP Calculators (MoHPC). Archived from the original on 2016-08-02. Retrieved 2016-08-02. http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/archv016.cgi?read=101928 ↩

  21. Rautenberg, Wolfgang (2004-05-09). "IOMAN - A small but powerful I/O manager for the HP49G/HP49g+". 5.2004. Archived from the original on 2016-08-02. Retrieved 2016-08-02. [2] /wiki/Wolfgang_Rautenberg ↩

  22. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩

  23. HP 82240B Infrared Printer (1 ed.). Corvallis, OR, USA: Hewlett Packard. August 1989. pp. 17–18. HP reorder number 82240-90014. /wiki/Hewlett_Packard ↩

  24. HP 48G Series – User's Guide (UG) (8th ed.). Hewlett-Packard. December 1994 [1993]. pp. 2–5, 27–16. HP 00048-90126, (00048-90104). Archived from the original on 2016-08-06. Retrieved 2015-09-06. [3] http://www.hpcalc.org/details.php?id=3937 ↩

  25. "Thimet Hewlett Packard HP 48S, SX, G, G+, GX, gII". Archived from the original on 2018-10-23. Retrieved 2014-01-20. https://web.archive.org/web/20181023044605/http://www.thimet.de/CalcCollection/Calculators/HP-48GX/Contents.htm ↩

  26. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩

  27. HP 82240B Infrared Printer (1 ed.). Corvallis, OR, USA: Hewlett Packard. August 1989. pp. 17–18. HP reorder number 82240-90014. /wiki/Hewlett_Packard ↩

  28. HP 48G Series – User's Guide (UG) (8th ed.). Hewlett-Packard. December 1994 [1993]. pp. 2–5, 27–16. HP 00048-90126, (00048-90104). Archived from the original on 2016-08-06. Retrieved 2015-09-06. [3] http://www.hpcalc.org/details.php?id=3937 ↩

  29. "Thimet Hewlett Packard HP 48S, SX, G, G+, GX, gII". Archived from the original on 2018-10-23. Retrieved 2014-01-20. https://web.archive.org/web/20181023044605/http://www.thimet.de/CalcCollection/Calculators/HP-48GX/Contents.htm ↩

  30. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩

  31. HP 82240B Infrared Printer (1 ed.). Corvallis, OR, USA: Hewlett Packard. August 1989. pp. 17–18. HP reorder number 82240-90014. /wiki/Hewlett_Packard ↩

  32. HP 48G Series – User's Guide (UG) (8th ed.). Hewlett-Packard. December 1994 [1993]. pp. 2–5, 27–16. HP 00048-90126, (00048-90104). Archived from the original on 2016-08-06. Retrieved 2015-09-06. [3] http://www.hpcalc.org/details.php?id=3937 ↩

  33. "Thimet Hewlett Packard HP 48S, SX, G, G+, GX, gII". Archived from the original on 2018-10-23. Retrieved 2014-01-20. https://web.archive.org/web/20181023044605/http://www.thimet.de/CalcCollection/Calculators/HP-48GX/Contents.htm ↩

  34. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩

  35. "Thimet Hewlett Packard HP 48S, SX, G, G+, GX, gII". Archived from the original on 2018-10-23. Retrieved 2014-01-20. https://web.archive.org/web/20181023044605/http://www.thimet.de/CalcCollection/Calculators/HP-48GX/Contents.htm ↩

  36. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩

  37. "Thimet Hewlett Packard HP 48S, SX, G, G+, GX, gII". Archived from the original on 2018-10-23. Retrieved 2014-01-20. https://web.archive.org/web/20181023044605/http://www.thimet.de/CalcCollection/Calculators/HP-48GX/Contents.htm ↩

  38. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  39. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  40. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  41. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  42. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  43. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  44. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  45. Croft, Colin (December 2006). hp 39gs and hp 40gs graphing calculators. Mastering the hp 39gs & hp 40gs - A guide for teachers, students and other users of the hp 39gs & hp 40gs (PDF). 1.0 (1st ed.). Hewlett-Packard Development Company, L.P. pp. 26, 221, 333. HP part number F2224-90010. Archived (PDF) from the original on 2016-03-03. Retrieved 2016-08-06. The original hp 38g only had the function INVERSE(…) and the -1 operator was added for convenience sake in the hp 39g, released in 2000. To do this the creators had to borrow one of the existing unused characters, the 3 character, and convert it into the -1 operator. However, they forgot to change it in the CHARS view and this error has never been fixed in any of the successive models! http://www.hp.com/ctg/Manual/c00829737.pdf ↩

  46. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩

  47. HP 82240A Infrared Printer (PDF) (2 ed.). Corvallis, OR, USA: Hewlett Packard, Portable Computer Division. October 1986. HP reorder number 82240-90001 (82240-90008). Archived (PDF) from the original on 2016-08-06. Retrieved 2016-08-06. https://members.ziggo.nl/kees.van.der.sanden/downloads/HP82240A_manual.pdf ↩

  48. Nungester, Rick (1988-08-18). "Infra-Red output converter". Luc Pauwels (published 2006-10-24). Archived from the original on 2016-08-06. Retrieved 2016-08-06. http://luc.xalasys.com/HP28 ↩

  49. HP-28S Advanced Scientific Calculator Reference Manual (PDF) (4 ed.). Hewlett-Packard. November 1988 [October 1987]. pp. 266–267. HP 00028-90068. Archived (PDF) from the original on 2015-06-08. Retrieved 2015-10-10. http://www.hp41.net/forum/fileshp41net/hp28sref.pdf ↩

  50. Nelson, Richard J. (2010). "Hewlett-Packard Calculator Firsts". Hewlett-Packard Development Company, L.P. Archived from the original on 2010-07-03. https://web.archive.org/web/20100703031935/http://h20331.www2.hp.com/Hpsub/cache/392617-0-0-225-121.html ↩