Martin: Printing Financial Calculator Sets New Standards for Accuracy and Capability, HP Journal, October 1977 (29), pp. It was equipped with a Sunplus SPLB20D2 [1] [18] with a 6502 core, larger memory (for up to 30 CFj registers [17] and 400 program steps) and more built-in functions. Its popularity has endured despite a relatively simple but iterative process such as amortizing the interest over the life of a loan, a calculation that modern spreadsheets can complete almost instantly, can take over a minute with the HP-12C. The first HP12c Platinum version (F2231A) did not have parentheses, which often led to awkward key sequences to solve problems in algebraic mode. The calculator's particular implementation of RPN exhibits an unusual behaviour of the CHS key different from that of the 12C and other classical RPN calculators.

It can display numbers in hexadecimal, decimal, octal and binary, and convert numbers from one base to another.It was such a successful model that Hewlett-Packard redesigned it from scratch, [1] added several new functions, and introduced it as the HP12c Platinum in 2003 as well as the HP12c Prestige. Please consider expanding the lead to provide an accessible overview of all important aspects of the article. Nearly identical in appearance, each model provided different capabilities and was aimed at different user markets.

A number of specialized functions are provided to assist the programmer, including left- and right-shifting, masking, and bitwise logical operations.

However, the subsequent revisions of the original 12C which switched to ARM-based processors have reversed that speed gap. This version (F2230A) was colloquially known as the " HP-12C+", although HP did not market it as a different product. Often referred to as a tool for "Old-ie Time-ies," critics of the HP-12C claim its early 1980s technology and style are antiquated.

Official emulators for the 12C and 15C are commercially available from Hewlett-Packard for Android [7] and iOS [8] devices. The 1977 October edition of the HP Journal contains an article by Roy Martin, the inventor of the simple method of operation used in HP financial calculators, which describes, in detail, the mathematics and functionality built by William Kahan and Roy Martin that is still used today. It features a gold-colored plate like the original 12C, but is otherwise like the fourth HP12c Platinum model (F2231AA). The calculator's part number and physical appearance didn't change except for a "Rev 2" plate on the bottom side. The HP-15C is a high-end scientific programmable with a root-solver and numerical integration, produced between 1982 and 1989.HP has (as of 2015) never made another programmer's calculator, but has incorporated the 16C's functions in later calculator models. Based on the same processor, a limited HP12c 30th Anniversary Edition (NW258AA) was introduced in 2011. After the introduction of the larger DM15L, DM41L and DM16L in 2015, the DM11L was added in January 2016 with the DM12L following in February.

Poor sales led to a very short market life, making it one of the most difficult of the series to find today.Over its lifespan, the proprietary bulk CMOS HP Nut (originally the 1LF5, then 1LM2) [1] processor's technology has been redesigned to integrate all the circuitry into a single chip (first the 1LQ9, then 1RR2) [1] and to refresh the manufacturing process (as the foundry could no longer manufacture the necessary chips, having moved on to making higher-density chips). There have been multiple revisions over the years, with newer revisions moving to an ARM processor running a software emulator of the original Nut processor. Due to its simple operation for key financial calculations, the calculator long ago became the de facto standard among financial professionals. As in the later revisions of the 12C, it features two parallel rather than only one CR2032 cells, but it continues to be based on the GPLB31A processor.