Assembler RECORD Structure

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Assembler RECORD Structure

It would be nice to have a more elegant method of specifying packed subfield of words and bytes. Declaring a RECORD in assembly language allows us the means of doing this very easily. It has the form: RecName RECORD field₁:size₁, ... field_n:size₁ We can initialize it as: someName RecName <1, 1, 1> This means that we can have:

DirDate	RECORD	Year:7, Month:4, Day: 5
modDate	DirDate	<1, 1, 1>

This will give us the three following items:

field	the number of bits that Field is from the right end of the word or byte
WIDTH Field	is the number of bits in Field
MASK Field	a bit mask which can be use to extract Field from its word or byte

This allows use to improve the program example2a with:

	mov	ax, modDate
	and	ax, MASK Month
	mov	cl Month
	shr	ax, cl
	mov	OKMon, ax

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