btfss f,7-bit_number

[robinfawell]

The line

btfss SM_DOUT_VALUE, 7-bit_number

Appears in all of the scan matrix versions  in the single shift step macro SM_BUTTON_HANDLER SHIFT MACRO bit_number

I have found

btfss f,  b where b = 0-7

Can anyone help

Robin

[nILS]

What exactly is the question?

[stryd_one]

Oh it's a 'jeopardy' game: What is the acronym for  "Bit Test F, Skip if Set" ? ;D

[bugfight]

who got an f on their bit test cause they skipped it??

[stryd_one]

LOL, me too, etc *whack*

[robinfawell]

I know what btfss means. My difficulty is with the second operand  "7-bit_number". Perhaps I have complicated this.  I was thinking "any 7 bit number", originally.

If I conclude that this is referring to the 7th bit of SM_DOUT_VALUE why not just write

btfss SM_DOUT_VALUE, 7

Robin

[nILS]

Well who says that bit_number is a constant? Assuming it's a variable

"btfss SM_DOUT_VALUE, 7-bit_number"

checks a different bit depending on the content of bit_number. If bit_number is 0 for instance it'll check the 7th bit, if it's 3 it'll check the 4th bit...

[robinfawell]

That is what I thought originally.  However if you search for "7-bit_number"  in all the files that comprise sm c example v1.zip there is only one file that contains "7-bit_number" and that file is sm fast.inc and in that file there is only one instance of "7-bit_number" and that line is the one referred to in the first instance.

This seems to discount that "7-bit_number" is a variable.

Robin

[nILS]

What I meant was bit_number is a variable. 7 is a constant  ;) 7 - bit_number is a combination of a constant and a variable and is hence variable.

[robinfawell]

Thanks Nils

bit_number is a variable and appears in several places in sm_fast.

It never occurred to me that the - was a minus sign.  I was thinking of it as a hyphen.

Robin

[nILS]

Hyphens cannot be used in variable names, only "A-Z", "a-z", "0-9" and "_" ;)

[robinfawell]

I should have remembered the syntax rules!

Robin