my41 is an advanced programmable and expandable RPN calculator for OS X.
- RPN logic with 4 element deep memory stack
- Functionally equivalent to the HP-41C/CV/CX
- Memory registers: 63..319
- Program steps: 441..2233
- Four module ports provide access to HP-41 expansion pacs (via MOD files)
- BEEP is not supported at the moment
- Problem with loading HEPAX module
What is RPN?
Reverse Polish notation (RPN) is a mathematical notation in which every operator follows all of its operands, in contrast to Polish notation, which puts the operator in the prefix position. It is also known as postfix notation and is parenthesis-free as long as operator arities are fixed. The description "Polish" refers to the nationality of logician Jan Lukasiewicz, who invented (prefix) Polish notation in the 1920s.
For example, in the expression 5 + 3 = 8 the '+' operator is placed between the 5 and the 3. Using RPN previous example would be expressed as 5 'Enter' 3 +
One of the discoveries of the community was that it was possible to exploit a bug in the program editor to assign strange functions to keys. The most important function was known as the byte jumper, a way to step partially through programming instructions and edit them in ways that were not otherwise allowed. The use of the resulting instructions was called synthetic programming.
Through synthetic instructions, a user could access memory and special status flags reserved for the operating system, and do very strange things, including completely locking the machine. It was possible to create sounds or display characters, and create animations not officially supported by the operating system. The system flags were also accessed as low-level shortcuts to boolean programming techniques. Hewlett-Packard did not officially support synthetic programming, but neither did it do anything to prevent it, and eventually even provided internal documentation to the user groups.
If you interested to do synthetic programming, you will probably want to use PPC ROM. The PPC ROM manual is available on Library page.
If the clock is active emulator syncs timer with computer's system time on ApplicationBecomeActive event.
Solved problem with CLOCK
Fixed a lot of bugs. This is Release Candidate version.
Start Text Editor (XEQ ED) bug fixed.
Removed a few nasty bug. Recommend everyone to download new version.
Fixed bug: EXIT from Text Editor (XEQ ED) turns off calculator
Fixed 'SETIME' crash
Fixed bug: USER-indicator stays lit, when the emulator turns Off via its ON-key
Fixed some immediate crashes.