HP 39gs
| Company type | Product line |
|---|---|
| Industry | Consumer electronics |
| Predecessor | HP 38G |
| Founded | 2000 |
| Products | Graphing calculators |
| Owner | Hewlett-Packard |
HP 39/40 series represents a line of graphing calculators developed by Hewlett-Packard, following the HP 38G model. This lineup consists of six variants that offer algebraic input methods and numerical analysis, with differing levels of symbolic computation support. Designed primarily for secondary education students, these calculators enable the transfer of APLETs or E-lessons through cable or infrared connections, facilitating enhanced mathematical understanding via graphical and numeric tools.
HP 39g
Introduced in 2000, the HP 39g (F1906A) includes the following features:
- CPU: 4 MHz Yorke processor based on the Saturn architecture
- Connectivity: Proprietary infrared and serial RS-232
- Memory: 256 KB RAM
- Display resolution: 131 × 64 pixels
- Comes with a protective hard cover
- Offers limited capabilities for symbolic equation solving
HP 40g
Launched simultaneously with the HP 39g in 2000, the HP 40g (F1907A) operates on the same system software but differs in hardware and software attributes.
Its hardware resembles that of the HP 49G/39G series and features a rubber keypad. This model incorporates the sophisticated computer algebra system (CAS) from the HP 49G, known as HP CAS. Unlike more advanced models, it does not include flags, simplifying mathematical analysis. The HP 40g lacks infrared communication and restricts users to managing only 27 variables. It provides a solver based on lists but is less suited for complex applications. While it is prohibited on certain standardized exams like the ACT, it has been permitted on the SAT since 2019.
Notable specifications:
- Matches HP 39g except for:
- Connectivity: Serial RS-232 only, no infrared
- Software: Includes an equation editor and advanced CAS functionality
HP 39g+
Released in September 2003, the HP 39g+ (F2224A) introduced upgraded hardware while retaining a similar software framework:
- CPU: Samsung S3C2410X at 75 MHz (ARM920T core)
- Memory: 256 KB RAM and 1 MB flash storage
- Communication: USB Mini-B port supporting Kermit or XModem protocols, plus IrDA (infrared)
- Power source: Three AAA batteries with a CR2032 battery for memory retention
- Screen size: 131×64 pixels
- No hard cover provided
- Symbolic equation solving remains limited
Although powered by an ARM processor, this device’s operating system emulates the Saturn chip at a faster rate than its predecessor, the original 39G. Unlike the HP 40g, this version excludes the CAS entirely rather than concealing it.
HP 39gs
The HP 39gs (F2223A), released in June 2006, offers these key features:
- CPU: Samsung S3C2410A running at 75 MHz (ARM920T core)
- Memory capacity: 256 KB RAM with an additional 1 MB flash memory
- Connectivity options: USB Mini-B port (compatible with Kermit/XModem protocols), IrDA infrared interface, and a 4-pin asynchronous 3.3 V TTL serial port (convertible to RS-232)
- Power supply: Four AAA batteries alongside a CR2032 for preserving memory
- Display resolution: 131×64 pixels
- Supplied with a hard protective cover
- Limited symbolic equation functionality
- Firmware updates can be installed via flash memory
Despite utilizing an ARM CPU, its operating system closely replicates that of the HP 39G by emulating the Saturn processor at increased speeds.
HP 40gs
Introduced in mid-2006, the HP 40gs (F2225A) presents several enhancements compared to the HP 39gs model:
- It offers 256 KB of RAM alongside an expanded 2 MB flash memory designed to accommodate CAS software
- Infrared communication capability is omitted
- The included software features an equation editor and a sophisticated CAS system
This model is powered by the same 75 MHz Samsung ARM920T processor found in the HP 39gs.
HP 39gII
Launched in October 2011, the HP 39gII (NW249AA) is equipped with an 80 MHz Freescale STMP3770 CPU based on the ARM926EJ-S architecture. It contains 256 KB of RAM and a 128 MB flash memory, with approximately 240 KB RAM and between 80 to 105 MB flash accessible to users. The device sports a high-resolution monochrome display with a pixel count of 256×128. Connectivity is provided through a USB-OTG Micro-AB interface.
The calculator’s BCD arithmetic libraries were redeveloped in platform-independent C for direct native operation, resulting in improved processing speeds compared to earlier emulated System RPL implementations. Its programming language, resembling Pascal, laid the groundwork for the HP Prime’s HP PPL. The system supports a stack depth of up to 128 levels and incorporates Unicode (UTF-16) encoding. Two versions exist, differing primarily in key labeling.
Plans for an upgraded "HP 39gII+" model featuring CAS functionality were discontinued after Freescale ceased production of the processor. This shift prompted HP to focus on developing the more advanced, color touchscreen HP Prime, which was released in 2013.
See also
- Comparison of HP graphing calculators
- HP calculators
- RPL character set
- newRPL (for HP 39g+, 39gs, 40gs)