HP 40gs
| Industry | Electronics, Computer hardware |
|---|---|
| Founded | January 1, 1939 |
| Founder | Bill Hewlett, Dave Packard |
| Headquarters | Palo Alto , United States |
| Products | Graphing calculators (including HP 39/40 series) |
HP 39/40 series represents a line of graphing calculators developed by Hewlett-Packard, succeeding the HP 38G. This lineup consists of six distinct models, all equipped with algebraic input modes and capable of performing numerical analysis, with varying degrees of symbolic computation. Designed primarily for high school education, these calculators enable users to download APLETs or E-lessons via cable or infrared, thereby facilitating enhanced mathematical learning through graphical visualization and numerical experimentation.
HP 39g
Introduced in 2000, the HP 39g (F1906A) offers the following specifications:
- CPU: 4 MHz Yorke processor based on the Saturn architecture
- Connectivity: Proprietary infrared interface and serial RS-232 port
- Memory: 256 KB RAM
- Display resolution: 131 × 64 pixels
- Comes with a protective hard cover
- Provides limited capabilities for symbolic equation processing
HP 40g
Also launched in 2000 alongside the HP 39g, the HP 40g (F1907A) runs on the same operating system but distinguishes itself through hardware-enabled software features.
Its hardware configuration aligns with that of the HP 49G/39G series and includes a rubberized keyboard. Unlike the HP 39g, this model incorporates the sophisticated computer algebra system (CAS) from the HP 49G, known as HP CAS. The HP 40g delivers a more straightforward mathematical analysis experience without customizable flags but lacks infrared connectivity and restricts users to managing only 27 variables. Its list-based solver and other limitations render it less appropriate for advanced applications. Notably, the HP 40g is prohibited on numerous standardized exams such as the ACT, although it has been permitted on the SAT since 2019.
Key features include:
- Identical hardware to HP 39g except:
- Connectivity: Omits infrared; includes serial RS-232
- Software: Equipped with an equation writer and advanced CAS capabilities
HP 39g+
Released in September 2003, the HP 39g+ (F2224A) introduces major enhancements:
- CPU: Samsung S3C2410X at 75 MHz with an ARM920T core
- Memory: 256 KB RAM plus 1 MB flash storage
- Communication options: USB Mini-B port supporting Kermit and XModem protocols, alongside IrDA infrared
- Power source: Three AAA batteries supplemented by a CR2032 battery for memory retention
- Display resolution remains at 131×64 pixels
- Does not include a hard cover
- Symbolic equation processing remains limited
While based on an ARM processor, its operating system closely resembles that of the HP 39g by emulating the Saturn CPU at increased clock speeds. Importantly, unlike previous models, the CAS functionality from the HP 40g is entirely omitted rather than simply disabled.
HP 39gs
The HP 39gs (F2223A), introduced in June 2006, is powered by a Samsung S3C2410A CPU running at 75 MHz with an ARM920T core. It includes:
- Memory: 256 KB RAM and 1 MB flash memory
- Connectivity: USB Mini-B port (compatible with Kermit or XModem protocols), IrDA infrared, and a four-pin asynchronous serial port
- Power: Four AAA batteries supported by a CR2032 backup battery
- Screen resolution: 131×64 pixels
- Supplied with a hard cover for protection
The flash memory allows for firmware updates in the future. Despite utilizing an ARM processor, its operating system emulates the Saturn chip at higher speeds similar to that found in the HP 39G. Symbolic equation capabilities remain limited.
HP 40gs
Launched in mid-2006, the HP 40gs (model F2225A) utilizes the same 75 MHz Samsung ARM920T processor found in the HP 39gs but offers double the flash memory at 2 MB to accommodate more sophisticated CAS applications. It is equipped with 256 KB of RAM yet does not include infrared communication capabilities. This model features an equation writer along with enhanced computer algebra system functions.
HP 39gII
The HP 39gII (NW249AA), released in October 2011, operates on an 80 MHz Freescale STMP3770 ARM926EJ-S CPU and comes with 256 KB RAM alongside 128 MB flash memory (users have access to roughly 240 KB RAM and up to 105 MB flash). It boasts a high-resolution monochrome display with a pixel dimension of 256×128 and supports USB On-The-Go through a Micro-AB port. The calculator’s BCD arithmetic libraries were rewritten in platform-independent C code for native execution, significantly improving performance compared to the previous System RPL emulation. Its programming language, resembling Pascal, served as a foundation for the HP Prime’s HP PPL. Additionally, it features a stack depth of 128 levels and supports Unicode (UTF-16). Two versions exist with minor differences in key labeling.
An advanced "HP 39gII+" version including CAS functionality was nearly finalized but ultimately shelved after Freescale discontinued the processor. This prompted HP to further redesign the concept, resulting in the release of the more sophisticated color touchscreen HP Prime in 2013.
See also
- Comparison of HP graphing calculators
- HP calculators
- RPL character set
- newRPL (compatible with HP 39g+, 39gs, and 40gs)