returned to the traditional RND() function

README.md

@@ -9,11 +9,11 @@ Luxferre's Truly Tiny BASIC (henceforth LTTB) is a lean dialect of the BASIC pro
 The LTTB specification expands upon the original Design Notes in the following manner:
 
 - Line numbers from 1 to 32767 are supported.
-- A special pseudo-variable `$` is introduced, which holds a random number from 0 to 9999.
 - Any invalid statement (including `REM`) can be used for comments.
 - No command can be abbreviated inside `IF` statements.
 - `LET` and `THEN` keywords are optional.
 - `IF` statements also allow inserting line numbers after `THEN`, making it possible to write self-modifying programs.
+- A special `RND(n)` function is introduced that generates a random number from 0 to `n-1`.
 - The `NEW` command is synonym to `CLEAR`.
 - The `BYE` command can be used to exit the interpreter.
 - In the environments that support file systems or some kind of external file I/O, the `LOAD` command can be used to load BASIC programs into memory, and the `SAVE` command can be used to save BASIC programs from memory.
@@ -41,7 +41,7 @@ Besides, the goal is not just to make one implementation and call it a day, but
 In general, you should be able to run anything compatible with:
 
 * the original [Design Notes](http://www.ittybittycomputers.com/IttyBitty/TinyBasic/DDJ1/Design.html) by Dennis Allison;
-* the original Tom Pittman's 6800TB (if the program doesn't have any `USR` or `RND` calls and has proper spacing between the command and the rest of the statement);
+* the original Tom Pittman's 6800TB (if the program doesn't have any `USR` calls and has proper spacing between the command and the rest of the statement);
 * the [Damian Gareth Walker's implementation](http://tinybasic.cyningstan.org.uk/), provided all program lines are properly numbered (because that implementation uses auto–numbering when loading the programs). 
 
 ### Will there be any TBX (Tiny BASIC Extended) or PATB (Palo Alto Tiny BASIC) compatibility?