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I believe your issue is that the structure size is still a byte. I'm not sure if there is a better way but you might want to look into doing something like this (Instead of a union):
Yes, I'm aware of the problem (see my first message). I would like to avoid using functions here, hence I was asking if there is any way to overcome this byte alignment.
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Hi!
We need to use custom structures of BITS (not BOOLs) in our projects. For example:
...and ST_7bit in the same way. This is mandatory due to requirements of certain devices.
I combine 3bit and 7bit with a further structure:
Then, I do a union of the combined structure with WORD.
This doesn't work as I would expect. st3bit is copied to WORD correctly but st7bit is byte-aligned to the higher byte of the WORD.
Example: uUnionTest.st3_7.st3bit.x1 TRUE --> wTest is 256.
Is there any way I could pack the bits and omit the byte-alignment?
Please provide ST_3bit_7bit code (copy/paste issue). Providing the expected bit partern over a word would also help.
Last edit: dFx 2020-03-23
Hi,
here's ST_3bit_7bit:
In pic1 the result is as expected.
In pic2 I would expect value 15.
Last edit: pekkallio 2020-03-23
I believe your issue is that the structure size is still a byte. I'm not sure if there is a better way but you might want to look into doing something like this (Instead of a union):
Last edit: Lo5tNet 2020-03-24
Yes, I'm aware of the problem (see my first message). I would like to avoid using functions here, hence I was asking if there is any way to overcome this byte alignment.