D50SH-12C - E-Machines Computers & Internet

There is no contrast adjustment possible with the 12c. Most of the time, faint displays are due to weak batteries or poor contact with the battery or batteries.

I take it you mean a 12C Platinum.

Press f ALG. ALG is the f-shifted function of the EEX key, just above the double-size ENTER key. This will switch the 12C Platinum from RPN mode to Algebraic mode, and ALG indicator will light up instead of the RPN indicator.

To switch back to RPN, press f RPN. RPN is the f-shifted function of the CHS key just above the EEX key.

On a 12C Platinum, press f [ALG]

On a non-Platinum you're stuck. It has only the RPN mode.

Sorry, but the 12C doesn't have a fraction mode.

The 12C is more expensive and more powerful than the BAII+Pro. The HP is also programmable, which the TI isn't. Starting from scratch (assuming you've never used a calculator before---a somewhat unreasonable assumption) the TI might be easier to learn, at least initially. But after a certain point, the HP will leave the TI behind. The HP is faster and more capable.

There are at least three different versions of the 12C available. There's the original 12C, the 12C Platinum, and the current 12C. The only way to tell the difference between the two non-Platinums is to look at the battery compartment---the original uses three button cells while the newer uses two coin cells. The newer one is MUCH faster. The Platinum, however, can use RPN or algebraic.

Unless your choice is limited to the 12C or the BAII (by the requirement of an exam, perhaps), you might want to look at the HP 20B and the HP 30B. Programmability aside, they're even more powerful and easier to use and faster than the 12C, and the 30B is also programmable.

There are other considerations, of course. Factors such as the feel of the keyboard, the 12C's landscape orientation as opposed to the others' portrait orientation, etc, are all matters of personal preference.

Disclaimer: I own multiple HP and multiple TI calculators. I tend to use HP calculators for calculating, while I use TI calculators to answer questions here at FixYa.

The HP 12c is a purely RPN calculator; it does not have an algebraic mode.

To switch the HP 12c Platinum to algebraic, press f [ALG].

Here is the link to the pdf manual for your HP12C.

I assume we're dealing with a 12C Platinum, since a 12C doesn't have a +"equal" sign configuration_.

Press f then RPN.

Are we dealing with a 12C Platinum instead of a 12C?

On a 12C Platinum in ALG mode, you don't use the ENTER key at all, but the = key.

I couldn't find any reference to a HP calculator model 12p.
There is a HP 12c financial calculator and a 12c Platinum financial calculator.
Check both models (for images, specifications, functions, user guides, etc.) :
HP 12c Financial Calculator
HP 12c Platinum Financial Calculator