# KB556: CV29 - Addition Method for Hexadecimal Users

This article was last updated on Aug. 15, 2011, 5:02 p.m. | Print Article | Leave Feedback

CV29 controls many aspects of the locomotive, including its decoder address (including two or four digit address) , normal direction of travel (NDOT), whether the locomotive opperates at 28 speed steps or 128 and others.

Some older Digitrax throttles use hexadecimal notation for programming.  This article is presented for the benefit of those who may still be using these throttles.  CAUTION: if you are NOT using a DT100 or DT200, please disregard this article to avoid confusion.

The table below shows each switch and its value if it is on or off.

Notice that if the switch is off the value is zero.

To determine the hexadecimal* value to program for your decoder just go down the list and add up the numbers for all the switches you want to set as ON.

CV29 Examples of CV Values:

Switch #

Characteristic if OFF

Value

if OFF

# Characteristic if ON

Value

If ON

01

NDOT forward

00

NDOT reverse

01

02

14 speed steps

00

28/128 speed steps

02

03

Analog mode conversion off

00

Analog mode conversion on

04

04

Speed table off

00

Speed table on

10

05

00

20

All Digitrax decoders are shipped with a factory programmed value of 06 in CV29. This gives the decoders the characteristics highlighted.

 Switch # Characteristic if OFF Value if OFF Characteristic if ON Value If ON 01 NDOT forward 00 NDOT reverse 01 02 14 speed steps 00 28/128 speed steps 02 03 Analog mode conversion off 00 Analog mode conversion on 04 04 Speed table off 00 Speed table on 10 05 2 digit addressing 00 4 digit addressing 20 Total "ON" Value to Program in CV29 x06 hex

Note: 06 hex is the same as 06 decimal A value of 27 programmed into CV29 will give you a decoder that has a normal direction of travel in reverse, operates in advanced 28/128 speed step mode, has analog mode conversion enabled, does not use a speed table and has 4 digit addressing.

 Switch # Characteristic if OFF Value if OFF Characteristic if ON Value If ON 01 NDOT forward 00 NDOT reverse 01 02 14 speed steps 00 28/128 speed steps 02 03 Analog mode conversion off 00 Analog mode conversion on 04 04 Speed table off 00 Speed table on 10 05 2 digit addressing 00 4 digit addressing 20 Total "ON" Value to Program in CV29 x27 hex

*The values shown on both tables are hexadecimal values. As you turn the throttle right hand knob to the right on a throttle that is using hexadecimal numbers, you will see 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 0A, 0b, 0c, 0d, 0E, 10, 11, 12 etc. Because the 6 & b look very similar on the display, be careful. If you use 0b, for example, as the value for CV29 you won't get the 06 effects you are expecting!