Primary cvs, Cv 17,18 extended address, Description – SoundTraxx Tsunami Steam Technical Reference User Manual

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Tsunami Technical Reference

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CV 17,18
Extended Address

Description

CV 17 and 18 make up a ‘paired’ CV, meaning that the two CV registers

taken together hold one piece of data; in this case, the 14-bit extended

decoder address:

CV 17 Extended Address MSB

CV 18 Extended Address LSB

A0-A15:

Extended Address Value

The extended address allows the decoder to be assigned one of 10,179

addresses ranging from 0xC000 to 0xE7FF (Note however, that most

command stations will only recognize addresses 0000 through 9999.). The

extended address will only be recognized by the decoder when CV 29, bit

5 is set to 1. Once this bit is set, the decoder will no longer recognize its

primary address until CV 29, bit 5 is cleared.

CV 17 contains the most significant byte and must be loaded with values

within the range of 0xC0 and 0xE7. CV 18 contains the least significant byte

and may contain any value.

To determine the extended address value, add the desired four-digit address

to the number 49152. Divide this number by 256 and record the quotient and

the remainder. CV 17 is then programmed with the quotient value and CV 18

is programmed with the remainder value.

Example: Compute CV 17 and 18 register values for extended address 7152.

1. Add 7152 to 49152:

Sum = 56304.

2. Divide 56304 by 256:

Quotient = 219 Remainder = 240

3. Program CV 17 to 219

4. Program CV 18 to 240

Note: Most command stations will handle these computations automatically

Primary CVs

Bit 7

Bit 0

A15

A14

A13

A12

A11

A10

A9

A8

Bit 7

Bit 0

A7

A6

A5

A4

A3

A2

A1

A0

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