Halcyon Calc operate on strings of characters, or "strings" for short. The following sections describe how to work with strings on the calculator:
A string is entered as a series of characters surrounded by double quote characters ("). To start entering a string, hit the "■"" button. Then, you can type whatever characters you want to be a part of the string. Optionally, you can finish the string with a hit of the "■"" button and "Enter", or just hit "Enter". The final double quote is assumed if you do not enter it.
When you hit the first ■"" button, the calculator goes into "alpha" entry mode. For more details of what that means, refer to the Command Line section of the UI Guide.
You can take any item from the top of the stack and convert it to a string by using the →STR operation from the String menu. This operation will take the item from the top of the stack and then push a string to onto the stack whose contents is the character representation of that number (ie how it appeared on the stack prior to this operation but with double quotes around it).
The alternate conversion is possible also. If you have a string at the top of the stack, you can use the STR→ operation from the String menu to convert it to the item or items it contains. This operation pops the string from the top of the stack. Then, the calculator parses that string as though it was just typed at the command line. The result of parsing the contents of the string is then pushed onto the stack. So, the string "123" will result in the real number 123 being pushed onto the stack.
There are no formatting options in the calculator for strings. Also, any numbers which appear in the string are not affected by the different formatting modes for numbers. The contents of a string is unchanged by these modes.
There are many operations which you can use when working with strings. You can use + to concatenate two strings together. Here are some links to reference material which are relevant for lists: