 TDS2020F TECHNICAL MANUAL Forth word list 0 to 3 Live website search Enter key words 0   - 0   Used so often that zero is defined as a constant.   0<                    ANS   n - flag   Flag is true if n is less than zero.   0<>                    ANS   x - flag   Flag is true if n is not zero, and flag is false if n is zero. The true/false status of the item on the stack is unchanged but 0<> may be necessary before a logical operation. E.g. : TEST   81A0 C@ 4 AND 0<>   81B0 C@ 8 AND 0<> AND ; This returns true if both bit 2 of input 81A0 and bit 3 of 81B0 are both logic 1. 0<> is equivalent to 0= 0= .   0=                    ANS   x - flag   Flag is true if x is equal to zero.   0>                    ANS   n - flag   Flag is true if n is greater than zero.   0AT   -   Used with LCD displays. Clears the user variable AT which determines where the next character on the LCD will be written. Sets the first position.   0TIME   -   Uses Free Running Timer 3. Use only in a colon definition together with ?TIME to measure execution time of a word in microseconds. Will not upset timekeeping of on-board clock. See ?TIME .   1   - 1   Used so often that one is defined as a constant.   1+                    ANS   n1 - n2   or u1 - u2   Add 1 to n1 or u1 giving the sum n2 or u2.   1-                    ANS   n1 - n2   or u1 - u2   Subtract 1 from n1 or u1 giving the difference n2 or u2.   2   - 2   Used so often that two is defined as a constant.   2!                    ANS   x1 x2 aa -   Store the 32-bit pair x1 x2 at aligned address aa with x2 at aa and x1 at aa+2.   2*                    ANS   x1 - x2   x2 is the result of shifting x1 one bit left, filling the vacated least significant bit with zero.   2+   n1 - n2   or u1 - u2   Add 2 to n1 or u1 giving the sum n2 or u2.   2-   n1 - n2   or u1 - u2   Subtract 2 from n1 or u1 giving the difference n2 or u2.   2/                    ANS   x1 - x2   x2 is the result of shifting x1 one bit right, leaving the most significant bit unchanged.   232OFF   -   Disconnect power from RS232 driver chip.   232ON   -   Connect power to RS232 driver chip.   2>R                    ANS   EXECUTION:   x1 x2 -   R: - x1 x2 Transfer cell pair x1 x2 to the return stack. Equivalent to SWAP >R >R .   2@                    ANS   aa - x1 x2   Fetch the 32-bit pair x1 x2 from aligned address aa. x2 is stored at aa and x1 at aa+2.   2CONSTANT                    ANS   d 'name' -   Create a definition for name with the execution action defined below.   name EXECUTION:   - d Place d on the stack.   2DEC,   -   Assembler instruction, see assembler section and ADD:Q in Programming Manual. ADD:Q # -2 in Hitachi code. Syntax examples: R2 2DEC, \ Subtract 2 from          \ register 2 B \$FF00 )) 2DEC, \ Subtract          \ 2 from byte at          \ address hex FF00   2DROP                    ANS   x1 x2 -   Drop the 32-bit pair x1 x2 from the stack.   2DUP                    ANS   x1 x2 - x1 x2 x1 x2   Duplicate the 32-bit pair x1 x2.   2INC,   -   Assembler instruction, see assembler section and ADD:Q in Programming Manual. ADD:Q # 2 in Hitachi code. Examples: R2 2INC, \ Add 2 to          \ register 2 B \$FF00 )) 2INC, \ Add 2 to      \ byte at address FF00   2LITERAL                    ANS   COMPILATION:   d - Append the run-time action to current definition. RUN-TIME:   - d Place d on the stack.   2OVER                    ANS   x1 x2 x3 x4 - x1 x2 x3 x4 x1 x2   Copy the 32-bit pair x1 x2 to the top of the stack.   2R>                    ANS   EXECUTION:   - x1 x2   R:   x1 x2 - Transfer cell pair x1 x2 from the return stack. Equivalent to R> R> SWAP .   2R@                    ANS   EXECUTION:  - x1 x2   R: x1 x2 - x1 x2 Copy cell pair x1 x2 from return stack to data stack. Equivalent to R> R> 2DUP >R >R SWAP   2ROT                    ANS   d1 d2 d3 - d2 d3 d1   Rotate the top three cell pairs.   2SWAP                    ANS   x1 x2 x3 x4 - x3 x4 x1 x2   Exchange the top two 32-bit pairs.   2VARIABLE                    ANS   'name' -   Create a definition for name. Reserve two cells of data space (uninitialised at compile-time). name EXECUTION:   - aa aa is the address of the first, lowest addressed, reserved cell. A program should initialise the contents.   3   - 3   Used so often that three is defined as a constant. 