Atlas 520099 manual Bit Decimal, Number Equivalent Values for, Calculation

Decoder for Atlas N Scale H15/16-44 Locomotives 13

Converting Binary Values of Individual Bits within a Configuration Variable into the Equivalent Decimal Value of the Entire CV

Reasons for Setting and Clearing the Individual Bits of a Configuration Variable

To make a DCC decoder perform in the manner that you wish, you sometimes need to set or clear individual bits of a CV. To program a DCC decoder using a DCC system that allows only the writing of decimal values into CVs (such as the Atlas Master Commander), it is first necessary to convert the values of all the individual bits of that CV that are to be set to the binary value 1 into their equivalent decimal values. It is then necessary to add together all of these equivalent decimal values.

Procedure for Converting Individual CV Bit Values into a Decimal Equivalent Value for the CV

The following table illustrates how to calculate the decimal value that must be written into a CV to set and/or clear a specified set of individual bits within that CV.

Each bit of a CV that is to be set to the	Bit	Decimal	Decimal
binary value “1” can be represented by the	Number	Equivalent	Values for
equivalent decimal number shown in the			CV
second column of this table. To determine			Calculation
	0	1
the equivalent decimal value to be written
into the CV, first write in column 3 of this	1	2
table the decimal equivalent values of all	2	4
the bits of the CV that are to be set to a	3	8
binary 1. Write nothing in column 3 for
	4	16
each bit of the CV that is to be cleared,
	5	32
i.e., set to a binary 0. Then add up all the
	6	64
numbers that you have written in column
3. The sum that you get is the equivalent	7	128
decimal value you need to write into the
CV.
		SUM:

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