HP-28S Quick Reference
See at the end of this document.
Famous calculator made by Hewlett-Packard from 1988 – 1992.
32768 bytes for stack, programs and data.
Approximately 31.6 kBytes available to the user.
Press and hold ON then press + or – to change the contrast.
The HP-28S is a stack-based calculator.
For details on using the stack see STACK Menu.
See System Operations. Note that a program or other lengthy
operations can usually be interrupted by pressing "ON".
Can be turned off by clearing flag 51, see Flags.
The main difference is the smaller memory of only 2 kByte.
And whereas the HP-28S comes with a software version "2BB" it is
"1BB" for the HP-28C.
At least four editions of the Reference Manual exist: Version 1 dated
October 1987 to version 4 dated November 1988.
This Quick Reference is based on my experience with a HP-28S version
"2BB". It is best described by edition 4 of the Reference Manual.
A. Thimet, V1.0, © 2003, all right reserved.
56 bit for real numbers, 12 decimal digits of precision, exponent
64 bit for binary numbers
Commands can be entered by typing their name explcitly.
Most commands and functions are organized in menus, some are
directly available on the keyboard. See Direct Key Commands.
SYSEVAL is the only command which neither accessible thru the
keyboard not thru a menu. See System Operations.
Some commands are present in multiple menus.