From: admin@nospicedham.127.0.0.1   
      
   On Sat, 15 May 2021 11:21:43 +0100   
   "Kerr-Mudd, John"  wrote:   
      
   > On Fri, 14 May 2021 21:53:32 +0200   
   > Terje Mathisen  wrote:   
   >   
   > > Robert Prins wrote:   
   > > > Is it possible to fit the conversion of a 16 bit signed integer to   
   > > > left-aligned ASCII without leading zeroes in just 65 bytes?   
   > >   
   > > Naively I would say yes: I assume you don't care about speed here?   
   > >   
   > > ;; AX has the value to be converted to ascii   
   > [code elided]   
   > I took the liberty of moving the "mov bx,10" out of the loop!   
      
   How embarrassing; needs bx setting if +ve!   
      
   > NASM .lst file:   
   >   
        1                                  org 0x100   
        2                                  cpu 8086   
        3   
        4                                  ;; AX has the value to be converted to   
   ascii   
        5                                  ;; Store the string to the buffer   
   pointed to by DI   
        6 00000000 B8FF7F                         mov ax,0x7FFF   
        7 00000003 BF[2F00]                       mov di,Ostr   
        8   
        9                                  putnum:   
       10 00000006 31C9                       xor cx,cx	; Count how many digits   
   we find   
       11 00000008 85C0                       test ax,ax	; Positive?   
       12 0000000A 7D06                        jge notneg   
       13   
       14                                  ;; Negative input value, so print a   
   '-' sign   
       15 0000000C C6052D                     mov byte [di],'-'   
       16 0000000F F7D8                       neg ax   
       17 00000011 47                         inc di   
       18                                  notneg:   
       19 00000012 BB0A00                     mov bx,10   
       20   
       21                                  next:   
       22                                  ;   xor dx,dx   
       23 00000015 99                         cwd          ; ok as hibit has been   
   removed   
       24 00000016 F7F3                       div bx   
       25 00000018 52                         push dx	; Remainder is the digit   
       26 00000019 41                         inc cx   
       27 0000001A 85C0                       test ax,ax	; Is it zero yet?   
       28 0000001C 75F7                        jnz next   
       29   
       30                                  dump_digits:   
       31 0000001E 58                         pop ax   
       32 0000001F 0430                       add al,'0'   
       33 00000021 AA                         stosb   
       34 00000022 E2FA                        loop dump_digits   
       35   
       36                                  convlth equ $-putnum   
       37   
       38 00000024 B82409                      mov ax,0x100*9+'$'   
       39 00000027 AA                          stosb   
       40 00000028 BA[2F00]                    mov dx,Ostr   
       41 0000002B CD21                        int 0x21   
       42 0000002D C3                          ret   
       43 0000002E 1E                      db convlth   
       44                                     Ostr equ $   
      
   >   
   > > That looks like 17 instructions, most of them two-byte, 5 one-byte and a   
   > > couple that are longer, so 32-35 bytes?   
   >   
   > 1E=30 bytes   
   >   
   >   
   > --   
   > Bah, and indeed Humbug.   
   >   
      
      
   --   
   Bah, and indeed Humbug.   
      
   --- SoupGate-Win32 v1.05   
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