Harry H. Arends wrote:

>> OK by now i am aware to be more specifik. The language is ASM.
>> The data to be sendout...

Can you better define what "sendout" is ?
How will it be sent ?
Using what interface ?

>> is in four 8 bit variables:
>> DATA0 contains all ones
>> DATA1 contains a 8 bit address (AAAAAAAA)
>> DATA2 contains a 8 bit command (DDDDDDDD)
>> DATA3 contains a bitwise exclusif OR from the DATA1 and DATA2
>>
>> The result should become
>> BYTE0 11110AAA

Let's number the bit positions 0-7.
Let's also assume that the bits are 76543210.

So DATA0.2 = BYTE1.7, DATA0.1 = BYTE1.6
and DATA0.0 = BYTE1.5, right ?

That could be done with a few bit-test and
bit set/clear instructions.

>> BYTE1 AAAAA0DD

OK, so rotate DATA1 3 positions to the left and
move to BYTE1.
Then set BYTE1.1 = DATA2.7 and BYTE1.1 = DATA2.7.

>> BYTE2 DDDDDD0E

Rotate DATA2 2 positions left and move to BYTE2.
Then set BYTE2.0 = DATA3.7.

>> BYTE3 EEEEEEE1

Rotate DATA3 1 position to the left and move
to BYTE3. Set BYTE3.0 = "1".

Then just do that in assembler.

*THEN* send BYTE0 to BYTE3 using whatever
method you'd like.

Jan-Erik.

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