Hex to Ascii

Thanks for the help. Yes I am writing in assembler. Any assembler examples anywhere ?

"tim" schreef in bericht news:biqqm4$97j$03$ snipped-for-privacy@news.t-online.com...

ASCII '0' is 0x30 or 48.

First break the hex value down into bytes, then for each byte use:

FirstChar = (hexval>>4) & 15; FirstChar += (FirstChar>9)? ('A'-10) : '0'; SecondChar = hexval & 15; SecondChar += (SecondChar>9)? ('A'-10) : '0';

or, what is probably less code:

static const char HexDigits[] = "0123456789ABCDEF"; FirstChar = HexDigits[ (hexval>>4) & 15 ]; SecondChar = HexDigits[ hexval & 15 ];

-Robert Scott Ypsilanti, Michigan (Reply through newsgroups, not by direct e-mail, as automatic reply address is fake.)

Here's the C code:

char hexd( char digit ) { return "0123456789ABCDEF"[ digit & 0xF ]; }

-- _ Kevin D. Quitt 91387-4454 snipped-for-privacy@Quitt.net 96.37% of all statistics are made up

oops, I took the first digit from one and the second from the other, (I guess you can see that!)

tim

A good place for examples of this sort of thing is the asm file for the Buffalo monitor.

One binary byte = 2 ascii characters (left half, right half) The code segment below does both. First call OUT_RB for the right half, restore the original byte in A, then call OUT_LB for the left half. OUT_ASC is just a subroutine that puts the resulting bytes somewhere.

; Convert A, BIN to ASCII (A is lost)

OUT_LB LSRA ; shift data to right LSRA ; " LSRA ; " LSRA ; " OUT_RB ANDA #0FH ; mask top half ADDA #30H ; \ convert to ascii CMPA #39H ; | BLE OUT_A ; | jump if 0-9 ADDA #07H ; / convert to hex A-F OUT_A JSR OUT_ASC ; output character RTS

Regards Paul Bealing

Since we're talking about 68xx tricks of the trade...

AND A #$0F ; mask off nibble ADD A #0 ; clear half-carry bit in condition code DAA ; result range -> 00 - 09, 10 - 15 ADD A #$F0 ; result range -> F0 - F9 carry clear, 00 - 05 carry set ADC A #$40 ; result range -> 30 - 39 (ASCII 0-9), 41 - 46 (ASCII A-F)

Mark Zenier snipped-for-privacy@eskimo.com Washington State resident

To be pedantic, there are no hex values. A nibble is a 4 bit binary value that can be _represented_ as a hexidecimal digit.

Paul Bealing writes: [snip]

Or convert both with:

OUT2HEX pshA bsr out_LB pulA bra out_RB

OUT_LB LSRA ; shift data to right LSRA ; " LSRA ; " LSRA ; " OUT_RB ANDA #0FH ; mask top half ADDA #30H ; \ convert to ascii CMPA #39H ; | BLE OUT_A ; | jump if 0-9 ADDA #07H ; / convert to hex A-F OUT_A jmp OUT_ASC ; output character

Not realy serious:

char s[11]; sprintf(s,"%x",value);

or save the branch:

out2hex psha lsra lsra lsra lsra bsr out_nibble1 ; no and needed ! pula out_nibble: anda #0xf out_nibble1: adda #0x30 cmpa #0x39 ble out_a adda #0x7 out_a: jmp out_asc

Now, that's a cool piece of code !

Anyone in alt.folklore.computers know who came up with this? As I remember, I first saw it in the debug monitor in the Poly 88 (a.k.a. Microaltair). An 8080 based S-100 machine. So the technique was from before 1977.

Mark Zenier snipped-for-privacy@eskimo.com Washington State resident

Might as well add the 8051 version I always use ...

H2ASC: anl A,#0FH add A,#90H da A addc A,#40H da A

Regards Peter Ihnat Uni of Wollongong