Loop code tutorial in PBCC50.

[hutch--]

This is a simple example that shows how common loop types are constructed in assembler.

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#IF 0  ' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    Build with PBCC50

    FUNCTION LIST
        1. cout     console display with C escape support
        2. pause    wait for a key press to continue
        3. sstr     convert a SIGNED integer to a basic string
        4. ustr     convert an UNSIGNED integer to a basic string
        5. atoi     convert a string to an UNSIGNED integer
        6. atol     convert a string to a SIGNED integer

#ENDIF ' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

FUNCTION PBmain as LONG

    #REGISTER NONE

    LOCAL svar as LONG
    LOCAL uvar as DWORD

    cout "\n\tTestbed for Assembler Programming in\n\tthe PowerBASIC Console Compiler PBCC50\n\n"

  ' ---------------------------------------------
  ' conversion tests string to integer to string
  ' NOTE
  ' you only use these functions on 32 bit values
  ' ---------------------------------------------
    svar = atol("-12345678")        ' ascii to LONG conversion
    longint$ = sstr(svar)           ' LONG to ascii conversion
    cout longint$

    uvar = atoi("4000000000")       ' ascii to DWORD conversion
    uint$ = ustr(uvar)              ' DWORD to ascii conversion
    cout uint$

    pause

    FUNCTION = 0

End FUNCTION

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    DECLARE FUNCTION cc_out CDECL LIB "MSVCRT.DLL" ALIAS "puts" (BYVAL ptxt AS DWORD) AS DWORD

SUB cout(a$)

  ' ***** Supported escapes *****
  ' \0 = ascii zero             0
  ' \t = tab                    9
  ' \n = newline               10
  ' \r = carriage return       13
  ' \q = double quote          34
  ' \\ = backslash             92
  ' *****************************

    #REGISTER NONE

    LOCAL src as DWORD
    LOCAL dst as DWORD
    LOCAL sln as DWORD

    src = StrPtr(a$)

    ! mov esi, src
    ! mov edi, src

  stlp:
    ! mov al, [esi]
    ! add esi, 1

    ! cmp al, "\"
    ! jne nxt

' ¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤

    ! cmp BYTE PTR [esi], "n"
    ! jne lb1
    ! add esi, 1
    ! mov BYTE PTR [edi], 10
    ! add edi, 1
    ! jmp stlp
  lb1:

    ! cmp BYTE PTR [esi], "r"
    ! jne lb2
    ! add esi, 1
    ! mov BYTE PTR [edi], 13
    ! add edi, 1
    ! jmp stlp
  lb2:

    ! cmp BYTE PTR [esi], "t"
    ! jne lb3
    ! add esi, 1
    ! mov BYTE PTR [edi], 9
    ! add edi, 1
    ! jmp stlp
  lb3:

    ! cmp BYTE PTR [esi], "0"
    ! jne lb4
    ! add esi, 1
    ! mov BYTE PTR [edi], 0
    ! add edi, 1
    ! jmp stlp
  lb4:

    ! cmp BYTE PTR [esi], "\"
    ! jne lb5
    ! add esi, 1
    ! mov BYTE PTR [edi], 92
    ! add edi, 1
    ! jmp stlp
  lb5:

    ! cmp BYTE PTR [esi], "q"
    ! jne lb6
    ! add esi, 1
    ! mov BYTE PTR [edi], 34
    ! add edi, 1
    ! jmp stlp
  lb6:

' ¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤=÷=¤

  nxt:
    ! mov [edi], al
    ! add edi, 1
    ! test al, al
    ! jnz stlp

    ! sub edi, src
    ! mov sln, edi

    cesc$ = left$(a$,sln)

    cc_out StrPtr(cesc$)

END SUB

' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    MACRO INPUT_HANDLE  = -10&
    DECLARE FUNCTION kbflush LIB "KERNEL32.DLL" ALIAS "FlushConsoleInputBuffer" ( _
                     BYVAL hConsoleInput AS DWORD) AS LONG
    DECLARE FUNCTION hStdIn LIB "KERNEL32.DLL" ALIAS "GetStdHandle" ( _
                     BYVAL nStdHandle AS DWORD) AS DWORD
    DECLARE FUNCTION SysYield LIB "KERNEL32.DLL" ALIAS "Sleep" ( _
                     BYVAL msWait AS DWORD) AS LONG
    DECLARE FUNCTION keypress CDECL LIB "MSVCRT.DLL" ALIAS "_kbhit" () as DWORD
    DECLARE FUNCTION putz CDECL LIB "MSVCRT.DLL" ALIAS "puts" (BYVAL ptxt AS DWORD) AS DWORD

' -------------------------------------------

SUB pause()

    txt$ = "Press any key to continue ...."
    putz StrPtr(txt$)
    kbflush hStdIn(INPUT_HANDLE)

  lbl0:
    SysYield 20
    keypress
    ! test eax, eax
    ! jz lbl0

END SUB

' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    DECLARE FUNCTION ltoa CDECL LIB "MSVCRT.DLL" ALIAS "_ltoa" ( _
                     ByVal lval as LONG,ByVal pstr as DWORD,ByVal radix as DWORD) as DWORD

' -------------------------------------------

FUNCTION sstr(ByVal lval as LONG) as STRING

    LOCAL astring as ASCIIZ * 32

    ltoa(lval,VarPtr(astring),10)

    FUNCTION = astring

End FUNCTION

' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    DECLARE FUNCTION c_ultoa CDECL LIB "MSVCRT.DLL" ALIAS "_ultoa" ( _
                     ByVal uint as DWORD,ByVal pstr as DWORD,ByVal radix as DWORD) as DWORD

' -------------------------------------------

FUNCTION ustr(ByVal uint as DWORD) as STRING

    LOCAL astring as ASCIIZ * 32

    c_ultoa(uint,VarPtr(astring),10)

    FUNCTION = astring

End FUNCTION

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    DECLARE FUNCTION c_atoi CDECL LIB "MSVCRT.DLL" ALIAS "atoi" (ByVal ptxt as DWORD) as DWORD

FUNCTION atoi(number$) as DWORD

    FUNCTION = c_atoi(StrPtr(number$))

End FUNCTION

' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤

    DECLARE FUNCTION c_atol CDECL LIB "MSVCRT.DLL" ALIAS "atol" (ByVal ptxt as DWORD) as LONG

FUNCTION atol(number$) as LONG

    FUNCTION = c_atol(StrPtr(number$))

End FUNCTION

' ¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤¤