View source for HP 48 series

{{short description|Series of graphing calculators}}
{{Distinguish|hp 48gII}}
{{More footnotes needed|date=November 2014}}
{{Use dmy dates|date=April 2019|cs1-dates=y}}
{{Use list-defined references|date=December 2021}}
{{Infobox Calculator
| name         = HP&nbsp;48&nbsp;series
| image        = HP48GX Calculator.jpg
| alt          = Picture of a Hewlett-Packard 48GX Calcularor
| caption      = HP&nbsp;48GX
| type         = [[Programmable calculator|Programmable]]<br />[[Scientific calculator|Scientific]]<br />[[Graphing calculator|Graphing]]
| entry        = [[RPN input mode|RPN]]
| introduced   = 1990
| discontinued = 2003<ref name="Paiva-2004" />
| predecessor  = [[HP-28S]]
| successor    = [[HP&nbsp;49G]]
| cost         = 350 USD
| manufacturer = [[Hewlett-Packard]]
| processor    = [[HP Clarke|Clarke]] [[HP 1LT8|1LT8]] ([[Saturn (microprocessor)|Saturn]] core for the HP48S series)<br />[[HP Yorke|Yorke]] <!--[[HP 1LT8|1LT8]]--><!-- The Yorke Saturn does *not* use the *Clarke
* 1LT8 core. It *does* use a core that's based on it though and which has several improvements. --> [[HP 00048-80063]] ([[Saturn (microprocessor)|Saturn]] core for the HP48G series)
| frequency    = 2–4&nbsp;MHz
| precision    = 12 [[Binary-coded decimal|BCD]] digits, exp ±499
| display_type = [[Twisted nematic field effect|TN LCD]]
| display_size = 131×64 [[pixel]]s
| prog_lang    = [[RPL (programming language)|RPL]] / [[Saturn (microprocessor)|Saturn]] [[Machine language]]
| memory_rom   = HP&nbsp;48S series: 256&nbsp;KB<br />HP&nbsp;48G series: 512&nbsp;KB
| memory_user  = HP&nbsp;48S series: 32&nbsp;KB<br />HP&nbsp;48G series: 32 to 128&nbsp;KB
| memory_extern= HP&nbsp;48SX: Ports 1 and 2 (merged): 256&nbsp;KB<br />HP&nbsp;48GX: Port 1: 128&nbsp;KB<br />Port 2: 4,096&nbsp;KB (4 MB)
| connection   = 4-pin [[RS-232]], [[Infrared port|HP-IR]]
| ports        = [[Serial transmission|Serial]], [[Infrared]], [[Kermit (protocol)]], ([[Xmodem]] added on G series)
| supply       = 4.5&nbsp;V (3× [[AAA battery]])
| weight       = 0.25&nbsp;kg (0.55&nbsp;lb)
| dimensions   = 17.9×7.9×2.8&nbsp;cm (7.05×3.11×1.1&nbsp;inch)
}}

The '''HP&nbsp;48''' is a series of [[graphing calculator]]s designed and produced by [[Hewlett-Packard]] from 1990 until 2003.<ref name="Paiva-2004" /> The series includes the '''HP&nbsp;48S''', '''HP&nbsp;48SX''', '''HP&nbsp;48G''', '''HP&nbsp;48GX''', and '''HP&nbsp;48G+''', the G models being expanded and improved versions of the S models. The models with an X suffix are expandable via special [[RAM]] (memory expansion) and [[ROM]] (software application) cards. In particular, the GX models have more onboard memory than the G models. The G+ models have more onboard memory only. The SX and S models have the same amount of onboard memory.

Note that the similarly named [[hp 48gII]] (2004) is not a member of the series but closely related to the [[HP 49/50 series|HP 49g+]].

The calculators use [[Reverse Polish Notation]] (RPN) and the [[RPL (programming language)|RPL]] programming language. The [[computer architecture|hardware architecture]] developed for the HP&nbsp;48 series became the basis for the [[HP&nbsp;38G]], with a simplified user interface and an [[infix notation|infix]] input method, and the [[HP&nbsp;49G]] with various software enhancements. Likewise, the hardware and software design of the HP&nbsp;48 calculators are themselves strongly influenced by other calculators in the HP line, most of all by the [[HP-18C]] and the [[HP-28 series]].

=={{anchor|F1630A|F1894A|F1895A|ASEE}}Models / Availability==
The HP 48SX was introduced on 1990-03-06.

Availability:
* 48SX: 1990–1993
* 48S: 1991–1993
* 48GX (F1895A): 1993–2003<ref name="Paiva-2004" />
* 48GX ASEE: 1993 (special edition labelled "1893 [[ASEE]] 1993 Shaping our world - Century II")
* 48G: 1993–2003<ref name="Paiva-2004" />
* 48G+ (F1630A, F1894A): 1998–2003<ref name="Paiva-2004" />

==Specifications==
The HP&nbsp;48 series' [[Saturn (microprocessor)|Saturn]] [[microprocessor]] is a hybrid [[64-bit]] / 20-bit [[CPU]] hardware-wise but acts like a [[4-bit]] processor in that it presents [[nibble]]-based data to programs and uses a nibble-based addressing system. The main registers A, B, C, D, along with temp registers R0, R1, R2, R3, and R4 are a full 64-bits wide, but the data registers D0 & D1 are only 20-bit. External logical data fetches are transparently converted to 8-bit physical fetches. The processor has a 20-bit [[address bus]] available to code but due to the presence of the high/low nibble selection bit, only 19 bits are available externally.

In both the HP&nbsp;48S/SX and G/GX series, the ''Saturn'' CPU core is integrated as part of a more complex [[integrated circuit]] (IC) package. These packages have codenames inspired by the members of the [[Lewis and Clark Expedition]]. The codename of the IC is ''Clarke'' in the S/SX, after [[William Clark]], and ''Yorke'' in the G/GX, after Clark's [[manservant]]. The previous series of Saturn-based ICs were codenamed ''Lewis'', after [[Meriwether Lewis]].

===Common for all models===
* CPU architecture: [[Saturn (microprocessor)|Saturn]]
* Screen resolution: 131×64 [[pixel]]s. There were 3 versions of the LCD display used across the range with each improving visibility and contrast over the predecessor.<ref>{{Citation |title=HP 48 Calculator Display Versions |url=https://www.youtube.com/watch?v=H4qZ0eSWoaI |language=en |access-date=2022-08-10}}</ref>
* Communication ports: 4-pin [[RS-232]] ([[Serial port]], standard UART at 1200 to 9600 bauds with option for parity (none/even/odd/mark/space)) and [[Infrared]] port (not [[IrDA]], similar to serial, zeroes are pulses with duration 1/8 of a full bit time)<ref name="hp48_io_technical_interfacing_guide" />
* Data bus width: [[8-bit]] (external)
* Maximum [[4-bit]]-cell address width: 20&nbsp;bits (leading to the address space shown next)
* Logical [[address space]]: 512&nbsp;KB
* Maximum register size: 64&nbsp;[[bit]] (both working and scratch registers)
* Available expansion card ports on X models: 2
* Expansion card pins: 40

==={{anchor|48S|48SX}}HP&nbsp;48S/HP&nbsp;48SX specific===
* CPU clock frequency: 2&nbsp;MHz
* Memory clock frequency: 2&nbsp;MHz
* CPU codename: [[HP Clarke|Clarke]] ([[Saturn (microprocessor)|Saturn]] [[HP 1LT8|1LT8]] core)
* Communication protocol(s): [[Kermit (protocol)]]
* On-board [[ROM]]: 256&nbsp;KB
* On-board [[RAM]]: 32&nbsp;KB
* Maximum additional memory per expansion card: 128&nbsp;KB (48SX only)
* ROM versions: A, B, C, D, E, (F,<ref name="FAQ48_3" /><ref name="Wickes_1991" />) J
* Orange and blue shift buttons

==={{anchor|48G|48GX|48G+}}HP&nbsp;48G/HP&nbsp;48GX/HP&nbsp;48G+ specific===
[[File:Hewlett-Packard 48GX Scientific Calculator Perspective.jpg|thumb|Hewlett-Packard 48GX Scientific Graphing Calculator]]
[[File:Memory collection (cropped) HP-48 RAM card 32kB.jpg|thumb|upright|32kB RAM card for HP 48SX and HP 48GX calculators]]

* CPU clock frequency: 3.68 to 4&nbsp;MHz
** Some claim that the frequency varies according to temperature<ref name="HPedia" />
** According to one of the engineers on the design team of the HP&nbsp;48G series (Dave Arnett), the yields for 4&nbsp;MHz CPUs were essentially separated into two bins: the ones closest to spec, generally near 3.93–3.94&nbsp;MHz, were reserved for the expandable models (GX), and those just slightly under spec were used for the non-expandable units (G). Eventually the yields improved and the CPUs which clocked closer to 4&nbsp;MHz were installed in the non-expandable units as well. The effects of (non-extreme) temperatures are almost negligible.{{Citation needed|date=May 2008}}
* Memory clock frequency: 2&nbsp;MHz
* CPU codename: [[HP Yorke|Yorke]] ([[Saturn (microprocessor)|Saturn]] <!--[[HP 1LT8|1LT8]]-->[[HP 00048-80063]]<!-- Again, the HP48G series Yorke SoC does not use the 1LT8 HP48S series Clarke SoC Saturn core. --> core)
* Communication protocol(s): [[Kermit (protocol)]], [[Xmodem]]
* On-board ROM: 512&nbsp;KB
* On-board RAM: 32&nbsp;KB (48G) or 128&nbsp;KB (48G+/48GX)
* Maximum additional memory for expansion card port&nbsp;1: 128&nbsp;KB
* Maximum additional memory for expansion card port&nbsp;2: 4&nbsp;MB (128&nbsp;KB addressable at any given time via [[bank switching]])
* ROM versions: K, L, M, P, R
* Purple and blue-green shift buttons. This is sort of a design error, since these colors may be indistinguishable for red-green color blind people

==Programming==
The HP&nbsp;48 series of calculators support a stack-based programming language named [[RPL (programming language)|RPL]], a supposed combination of [[Reverse Polish notation]] (RPN) and [[Lisp programming language|Lisp]]. RPL adds the concepts of lists and functions to [[Stack (abstract data type)|stack]]-based programming, allowing the programmer to pass unevaluated code as arguments to functions, or return unevaluated code from a function by leaving it on the stack.

RPL comes in two flavors: ''User RPL'' and ''System RPL''. ''User RPL'' is the language that a user can program directly on the calculator. ''System RPL'' requires an external compiler; this may be done on the calculator with a third-party utility, or on another machine. The two languages vary mainly in the number of low-level operations available to them. ''User RPL'' does not expose any commands that do not check their arguments. Consequently, ''User RPL'' programs cannot normally crash the calculator (and are therefore slower than ''System RPL'' programs), whereas a ''System RPL'' program that invokes a command with incorrect arguments will almost certainly leave the calculator in a state which requires a full memory reset.

It is also possible to program the HP&nbsp;48 directly in [[HP Saturn]] [[assembly language]]. This can be done either via user-supplied on-calculator tools (e.g. Jazz), or on another machine using user-supplied tools or those published directly by Hewlett-Packard (e.g. SASM et al.).

==Emulators==
* [http://hp.giesselink.com/emu48.htm Emu48] for Windows
* [https://www.hpcalc.org/details/3674 Alcuin] for Commodore Amiga
* [https://web.archive.org/web/20061113202408/http://x48.berlios.de/ X48] for Mac OS X, POSIX (Unix/Linux)
* [https://github.com/dparnell/i48 i48 - HP48GX emulator for iOS, based on X48]
* [http://www.mksg.de/ m48 – HP48 emulator for the iPhone, based on Emu48]
* [https://play.google.com/store/apps/details?id=org.ab.x48 Droid48 – HP48G Emulator for Android, based on X48]
* [https://play.google.com/store/apps/details?id=org.czo.droid48sx droid48sx – HP48SX Emulator for Android, based on Droid48]
* [http://www.courbis.fr/Emulateur-decompilateur-Saturn.html An HP48 emulator – decompiler] for Unix/Linux or Windows (using Cygwin) by [[Paul Courbis]]

== In popular culture ==
* An HP&nbsp;48 can be seen in the 2012 movie ''[[The Amazing Spider-Man (2012 film)|The Amazing Spider-Man]]'' and its [[The Amazing Spider-Man 2|sequel]].<ref name="techpoweredmath" />

==See also==
* [[Comparison of HP graphing calculators]]
* [[HP calculators]]
* [[RPL character set]]
* [[DB48X]]
* [[newRPL]]

==References==
{{reflist|refs=
<ref name="FAQ48_3">{{cite web |title=HP48 FAQ Section 3: Questions about ROM versions |work=Official HP48 FAQ - Answers to Frequently Asked Questions about the HP48 |author-first1=André |author-last1=Schoorl |author-first2=Keith |author-last2=Maddock |author-first3=Darryl |author-last3=Okahata |date=2000-04-14 |version=4.62 |orig-year=1997<!-- possibly earlier --> |editor-first=Eric |editor-last=Rechlin |publisher=HP Calculator Archive |volume=3 |url=http://www.hpcalc.org/hp48/docs/faq/48faq-3.html |access-date=2015-09-12 |url-status=live |archive-url=https://web.archive.org/web/20160820050132/http://www.hpcalc.org/hp48/docs/faq/48faq-3.html |archive-date=2016-08-20}}</ref>
<ref name="hp48_io_technical_interfacing_guide">{{cite web |title=HP 48 I/O Technical Interfacing Guide|url=https://www.hpcalc.org/hp48/docs/misc/io2.txt |website=hpcalc.org |publisher=Hewlett-Packard |access-date=2020-09-12|date=1990-06-14}}</ref>
<ref name="HPedia">{{Cite web|url=http://www.hpcalc.org/hp48/docs/hpedia/|title=HPedia: The HP Calculator Encyclopedia}}</ref>
<ref name="Paiva-2004">{{cite web |title=The End of An Era - On the genesis, life and death of the HP 48 |author-first=Joseph V. |author-last=Paiva |date=2004-10-01 |website=Point of Beginning (PoB) |publisher=BNP Media |url=http://www.pobonline.com/articles/85345-the-end-of-an-era |access-date=2015-10-20 |url-status=live |archive-url=https://web.archive.org/web/20160820050249/http://www.pobonline.com/articles/85345-the-end-of-an-era |archive-date=2016-08-20}}</ref>
<ref name="techpoweredmath">{{Cite web|url=https://www.techpoweredmath.com/spidermans-dad-hp-calculator-fan/|title = Spiderman's Dad an HP Calculator Fan?}}</ref>
<ref name="Wickes_1991">{{cite web |author-first=William C. |author-last=Wickes |title=HP 48 Version F: False Alarm |date=1991-03-12 |id=hpcvra.cv.hp.com item: 2404 |work=comp.sys.handhelds |url=http://www.hpcalc.org/hp48/docs/misc/revf.txt |access-date=2016-08-20 |url-status=live |archive-url=https://web.archive.org/web/20160428185955/http://www.hpcalc.org/hp48/docs/misc/revf.txt |archive-date=2016-04-28}}</ref>
}}

==Further reading==
* {{cite book |title=HP&nbsp;48G Series – User's Guide (UG) |publisher=[[Hewlett-Packard]] |edition=8th |date=December 1994 |id=HP 00048-90126, (00048-90104) |orig-year=1993<!-- edition 1 (1993-05) --> |url=http://www.hpcalc.org/details.php?id=3937 |access-date=2015-09-06 |url-status=live |archive-url=https://web.archive.org/web/20160806145719/http://www.hpcalc.org/details.php?id=3937 |archive-date=2016-08-06}} [http://www.hpcalc.org/hp48/docs/misc/hp48gug.zip<!-- https://web.archive.org/web/20160528071119/http://www.hpcalc.org/hp48/docs/misc/hp48gug.zip -->]
* {{cite book |title=HP&nbsp;48G Series – Advanced User's Reference Manual (AUR) |publisher=[[Hewlett-Packard]] |edition=4th |date=December 1994 |id=HP 00048-90136, 0-88698-01574-2 |orig-year=1993<!-- edition 1 (1993-07) --> |url=http://www.hpcalc.org/details.php?id=6036 |access-date=2015-09-06 |url-status=live |archive-url=https://web.archive.org/web/20160806145723/http://www.hpcalc.org/details.php?id=6036 |archive-date=2016-08-06}} [http://www.hpcalc.org/hp48/docs/misc/hp48gaur.zip<!-- https://web.archive.org/web/20160317061852/http://www.hpcalc.org/hp48/docs/misc/hp48gaur.zip -->]
* {{cite journal |author-first1=William C. |author-last1=Wickes |author-first2=Charles M. |author-last2=Patton |title=The HP&nbsp;48SX Scientific Expandable Calculator: Innovation and Evolution |publisher=[[Hewlett-Packard]] |journal=[[Hewlett-Packard Journal]] |volume=42 |issue=3 |year=1991 |pages=6&ndash;12 |url=http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1991-06.pdf |access-date=2015-09-06 |url-status=live |archive-url=https://web.archive.org/web/20160424213440/http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1991-06.pdf |archive-date=2016-04-24}}
* {{cite book |title=HP48 Machine Language - A Journey to the Center of the HP 48s/sx |author-first1=Paul |author-last1=Courbis |author-link1=Paul Courbis |author-first2=Sébastien |author-last2=Lalande |translator-first=Douglas R. |translator-last=Cannon |publisher=Grapevine Publications, Inc. |publication-place=Corvallis, Oregon, USA |edition=2nd |date=2006-06-25 |orig-year=1993 |oclc=34148948 |url=http://www.courbis.fr/spip.php?article21 |access-date=2015-09-06}} [http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_001_062.pdf<!-- https://web.archive.org/web/20160326063356/http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_001_062.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_063_121.pdf<!-- https://web.archive.org/web/20160326065052/http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_063_121.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_122_157.pdf<!-- https://web.archive.org/web/20160326062730/http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_122_157.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_158_210.pdf<!-- https://web.archive.org/web/20160326064425/http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_158_210.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_211_330.pdf<!-- https://web.archive.org/web/20160326062836/http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_211_330.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_331_397.pdf<!-- https://web.archive.org/web/20160326060426/http://www.courbis.fr/Data/Books/Pdfs_72/hp48ml/hp48ml_72x72_331_397.pdf -->] (First edition: [https://books.google.com/books?id=-pDqsUszxc4C])
* {{cite book |title=Voyage au centre de la HP48 s/sx |author-first1=Paul |author-last1=Courbis |author-link1=Paul Courbis |author-first2=Sébastien |author-last2=Lalande |language=fr |edition=3rd |version=3.02 |date=2006-06-25 |orig-year=1991 |publisher=Editions Angkor |publication-place=Paris, France |isbn=2-87892-003-1 |oclc=29640044 |url=http://www.courbis.fr/spip.php?article20 |access-date=2015-09-06}} [http://www.courbis.fr/Data/PDFS/Voyage48s/Voyage48s_72x72_001_060.pdf<!-- https://web.archive.org/web/20160330052750/http://www.courbis.fr/Data/PDFS/Voyage48s/Voyage48s_72x72_001_060.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_061_130.pdf<!-- https://web.archive.org/web/20160330052201/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_061_130.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_131_218.pdf<!-- https://web.archive.org/web/20160330052947/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_131_218.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_219_276.pdf<!-- https://web.archive.org/web/20160330052610/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_219_276.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_277_318.pdf<!-- https://web.archive.org/web/20160330052549/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_277_318.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_319_374.pdf<!-- https://web.archive.org/web/20160330052904/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_319_374.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_375_428.pdf<!-- https://web.archive.org/web/20160330051949/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48s/Voyage48s_72x72_375_428.pdf -->]
* {{cite book |title=Voyage au centre de la HP48 g/gx |author-first=Paul |author-last=Courbis |author-link1=Paul Courbis |language=fr |edition=3rd |version=3.05 |date=2006-06-25 |orig-year=1993 |publisher=Editions Angkor |publication-place=Paris, France |isbn=2-87892-006-6 |oclc=29640044 |url=http://www.courbis.fr/spip.php?article18 |access-date=2015-09-06 |url-status=live |archive-url=https://web.archive.org/web/20160806140746/http://www.webring.org/l/rd?ring=hp48;id=100;url=http%3A%2F%2Fwww%2Ecourbis%2Efr%2FVoyage%2Dau%2Dcentre%2Dde%2Dla%2DHP48%2Dg%2Dgx%2C18%2Ehtml |archive-date=2016-08-06}} [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_001_056.pdf<!-- https://web.archive.org/web/20160328042616/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_001_056.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_057_106.pdf<!-- https://web.archive.org/web/20160328043156/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_057_106.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_107_156.pdf<!-- https://web.archive.org/web/20160328044320/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_107_156.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_157_206.pdf<!-- https://web.archive.org/web/20160328043839/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_157_206.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_207_256.pdf<!-- https://web.archive.org/web/20160328042446/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_207_256.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_257_306.pdf<!-- https://web.archive.org/web/20160328043107/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_257_306.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_307_356.pdf<!-- https://web.archive.org/web/20160328043922/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_307_356.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_357_406.pdf<!-- https://web.archive.org/web/20160328042735/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_357_406.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_407_456.pdf<!-- https://web.archive.org/web/20160328043129/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_407_456.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_457_506.pdf<!-- https://web.archive.org/web/20160328042519/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_457_506.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_507_556.pdf<!-- https://web.archive.org/web/20160328043547/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_507_556.pdf -->] [http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_557_608.pdf<!-- https://web.archive.org/web/20160328043842/http://www.courbis.fr/Data/Books/Pdfs_72/Voyage48g/Voyage48g_72x72_557_608.pdf -->]
* {{cite book |title=Le compagnon de Voyage de la HP48 G/GX |author-first1=Paul |author-last1=Courbis |author-link1=Paul Courbis |author-first2=Cyrille |author-last2=de Brébisson |author-link2=Cyrille de Brébisson |language=fr |date=March 1994 |publisher=Editions Angkor |publication-place=Paris, France |isbn=2-87892-007-4 |url=http://www.courbis.fr/spip.php?article19 |access-date=2015-09-06 |url-status=dead |archive-url=https://web.archive.org/web/20160806135932/http://www.courbis.fr/Le-compagnon-de-voyage-de-la-HP48.html |archive-date=2016-08-06}} [http://www.lmet.fr/GSWeb/lmet.gswa/9/dr/CSHOPDirectAccess/search?baseListID=searchModel&searchType=searchByAll&resultsPageName=&resultsDisplayTemplateID=&searchedText=2-87892-007-4<!-- https://web.archive.org/web/20160806140445/http://www.lmet.fr/GSWeb/lmet.gswa/9/dr/CSHOPDirectAccess/search?baseListID=searchModel&searchType=searchByAll&resultsPageName=&resultsDisplayTemplateID=&searchedText=2-87892-007-4 -->]
* {{cite journal |author-first=Diana K. |author-last=Byrne |title=An Advanced Scientific Graphing Calculator: A concise treatment of design objectives, major engineering decisions, and the hardware/software of the HP&nbsp;48G/GX, compared to the S/SX |date=1994 |publisher=[[Hewlett-Packard]] |journal=[[Hewlett-Packard Journal]] |volume=45 |issue=4 |pages=6–22 |url=http://www.hpl.hp.com/hpjournal/94aug/aug94.htm |access-date=2015-09-06 |url-status=live |archive-url=https://web.archive.org/web/20160806144834/http://www.hpl.hp.com/hpjournal/94aug/aug94.htm |archive-date=2016-08-06}}
* {{cite web |title=Guide to the Saturn Processor (With HP48 Applications) |author-first=Matthew |author-last=Mastracci |date=1998 |orig-year=1995 |version=1.0b |url=http://www.grack.com/downloads/hp48/saturnguide/saturn.txt |access-date=2006-05-03 |url-status=dead |archive-url=https://web.archive.org/web/20160806130017/https://grack.com/writing/saturn/ |archive-date=2016-08-06}}

==External links==
{{Commons category|HP-48|HP 48}}
* [http://www.hpmuseum.org/hp48s.htm The Museum of Hewlett-Packard Calculators: HP 48S/SX]
* [http://holyjoe.net/hp/HP48.htm The HP48 Goodies Page]
* [http://www.hpcalc.org The HPCALC.org web site]
* [http://www.faqs.org/faqs/hp/hp48-faq HP48 FAQ (including program list)]

{{HP calculators}}
{{Authority control}}

{{DEFAULTSORT:Hp 48 Series}}
[[Category:Graphing calculators]]
[[Category:HP programmable calculators|48]]
[[Category:Products introduced in 1990]]