Help needed with my new decoder R8249

[Jeditommo]

Have just fitted an R8249 to my loco and the direction is reversed so when I select forward it goes in reverse and vice versa. How can I swap this around, I am using an NCE powercab. Thanks in advance

[Chrissaf]

You can either open up the loco and swap the connections to the electric motor.

OR

You can amend Bit 0 of CV29 [that is to say read the current value of CV29 and make an amendment to its value so that the Bit 0 value in the CV29 Byte is toggled from 0 to 1 OR 1 to 0 depending upon its current setting].

The online CV29 Calculator will explain all.

DCC CV29 Calculator

Extract below from calculator page.

Read your current value for CV29 and enter that value in the yellow highlight box, then click the 'Back Calc' button [red highlight].

This will populate the check boxes of the current CV29 options that have been set. Change the value of Bit 0 by either ticking or unticking the Bit 0 check box and a new value for CV29 will be shown in the yellow highlighted box. Then use your NCE PowerCab to write this new value to CV29 in your decoder.

Purely as an example. If your current value of CV29 is 6, then the process above will generate a new value of 7 to write to the decoder. If the current value of CV29 is already 7, then a new value of 6 will be generated.

An alternative method is to read the value of CV29. If CV29 is an even number, then make it an odd number by adding 1 to its value. If CV29 when read is already an odd number, then make it an even number by taking 1 away from its value [do not make CV29 even by adding a 1].

[Jeditommo]

Thanks all sounds good so will give it a go.

[Jupiter 1707822591]

With a powercab do this

Select the loco you want to alter

Press Enter .

Press 3

Display should display. Dir bit

Press 1

Loco will change direction .

Scroll options to escape .

[Jeditommo]

Have now resolved this thank you 🙏

[Hipwell]

Or of your using a honrby select controller just hold 0 and a direction arrow to swap it over