Byte to Hex

[enigma]

Hi all

I`m grabbing the serial number from an iButton in 6 array bytes. The full number is 12 digits, 2 per byte. Normally I output the number by serial using the HEX2 prefix to give 00 to FF from each byte. I need to write this number now to a OSD I.C which requires 12 separate bytes of data. I`ve looked at this for an age and I`m sure there must be a simple way to get two hex bytes from a single byte value but I cant discover it.
Example, the last 2 bytes returned from the iButton may be in Hex 2B 1A. I need this expressed in 4 bytes 2, B, 1, A Any ideas?
Regards Pete

[aerostar]

Off the top of my head........untested !!!!!!

Use nibbles

value = 2B

nibble = value >>4
go do lookup
nibble= value & %1111
go do lookup

findascii
Lookdown nibble,["0123456789ABCDEF"],asciichar


so
2B is binary %101011

shift right 4 =%0010
do the look down which returns 2 in ascii

nibble= value & %1111 = %1011
do the look down which returns B in ascii


Lookdown lownibble,["0123456789ABCDEF"],asciichar

[Dave]

enigma, Here is a subroutine I use to output ascii equivalent data for a word in hex:

'************************************************* ********************
HEXOUT: 'DECODE WORD INTO HEX CHARACTERS AND OUTPUT
'************************************************* ********************
'data to decode is placed in variable SCRATCH
'TX_CHAR is decodes ascii character

JUNK = 3 'number of hex characters
WHILE JUNK < 255
BITS4 = SCRATCH >> (4 * JUNK) 'MOST SIGNIFICANT 4 BITS
BITS4 = BITS4 & $0F
IF BITS4 < 10 THEN
TX_CHAR = BITS4 + $30
GOSUB SNDCHAR: 'INCREMENT BUFFER POINTERS
ELSE
TX_CHAR = (BITS4 - 10) + $41
GOSUB SNDCHAR: 'INCREMENT BUFFER POINTERS
endif
JUNK = JUNK -1
WEND
RETURN

Enjoy...

[Art]

This isn’t tested, but I believe it will split them,
but unsure if you meant ASCII values rather than these real values.



bytea = $2B

byteb = bytea >> 4
bytea = bytea - (byteb << 4)

‘ byteb = $02
’ bytea = $0B

[Art]

If that were to be output as a pair of ASCII bytes, I might go (after the above code)..


IF bytea > 9 THEN
bytea = bytea + $07
ENDIF
bytea = bytea + $30

IF byteb > 9 THEN
byteb = byteb + $07
ENDIF
byteb = byteb + $30

[pedja089]

Or simple use arraywrite:
OutputArray VAR BYTE[6]
ARRAYWRITE OutputArray,[HEX2 byte1, HEX2 byte2,..., HEX2 byte6]

[richard]

Or simple use arraywrite:
OutputArray VAR BYTE[6] ???
ARRAYWRITE OutputArray,[HEX2 byte1, HEX2 byte2,..., HEX2 byte6]


OutputArray VAR BYTE[12]

[mpgmike]

You might try using:

HEX1 VAR WORD
HEX2 VAR WORD

BYTE1 VAR BYTE (etc)

BYTE1 = HEX1.HIGHBYTE
BYTE2 = HEX1.LOWBYTE