Remote Processing Coorporation RPC-320 Specifiche Scaricare il pdf (Pagina 155)

Commands - 125

On power–up, you have 100 bytes of string space. You can change this with the CLEAR statement.

(Beneath the string area is the stack).

Thus, unused RAM extends from the top of the array space to the bottom of the stack.

EXAMPLE 1: 10 A = 1.1

20 B = VARPTR(A)

30 PRINT B ;

40 FOR X = 0 TO 3

50 PRINT PEEK(B+X) ;

60 NEXT : PRINT

RUN

17487 205 204 12 129

This example is for a simple numeric variable. The first number printed is the address of the first

byte of the floating point representation of the number, or “1.1”. This is the same as shown on the

previous page.

EXAMPLE 2: 10 H(0) = 1.1

20 Z = VARPTR(H(0))

30 PRINT Z

40 PRINT PEEK(Z) ; PEEK(Z+1) ; PEEK(Z+2) ; PEEK(Z+3)

RUN

17512

205 204 12 129

This routine returns the address of the first element of array H. The next element, if present, would

be at address 17004, the next at 17008, and so forth.

EXAMPLE 3: Addresses of array variables change each time a simple variable is assigned. For example:

10 T(0) = 0

20 PRINT VARPTR(T(0))

30 W = 0

40 PRINT VARPTR(T(0))

RUN

17484

17490

In this example, the variable W is first used after the array address was printed. Thus the array

address is shifted by the six bytes required for a simple variable.

EXAMPLE 4: 10 A$ = "Tuesday"

20 R = VARPTR(A$)

30 PRINT CHR$(PEEK(R))

In this case, new variables are declared after VARPTR returned the address. Unlike the array case,

the value returned will not change.

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Remote Processing Coorporation RPC-320 Specifiche Pagina 155