Digitrax Zephyr OPS Mode Decoder Programming

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Setting a four digit address using a Digitrax Zephyr, Zephyr Xtra or Zephyr Express command station. Blast Mode will be used.

The Digitrax Zephyr is also known as the DCS50, DCS51 (Xtra) or DCS52 (Express). For the most part they are the same unit.

For reference:

  • Four digit address/Long Address/Extended Address mean any address between 128 to 9999
    • Digitrax systems can only address to 9983)
  • Two Digit Address/Short Address/Primary Address refer to any address from 1-127.


This article documents how to program a QSI decoder installed in an Atlas brand locomotive using a Digitrax Zephyr or Zephyr Xtra DCC system. Atlas has used QSI for OEM decoders for a number of years. This procedure is based on a document published by Atlas.

If you want to read the original documents: Original Document

As always, refer to your owners/users manual, both for the decoder and your DCC system.

Programming Four Digit Addresses on the Mainline Using the Digitrax Zephyr or Zephyr Xtra DCC System

1. Place the locomotive on the main track and run it on DCC using address three (03), or whatever address was programmed into the locomotive decoder. If you can’t determine the address, reset the locomotive with the magnetic wand on a Direct Current powered track. Then test the locomotive on the main track with DCC using address three to ensure the reset worked.

  • Address three (03) is the default address every decoder is set to. Resetting the decoder will force all the settings back to their factory defaults, including the address the decoder responds to.

2. If your locomotive has a QSI sound decoder, keep the locomotive on the main line and use Operations Mode programming to set CV62 to 0 (zero). This step maximizes the probability that CV29 will be correctly set to its four digit address value to 38 (thirty eight) in Step 8 below.

Setting Blast Mode

3. To set the Option Switch #7 (seven) to on so that you can use Digitrax’s Blast Mode programming feature:

  • a. Press the PROG key.
  • b. Press the SWITCH key.
  • c. Using the keyboard enter 07 (zero seven).
  • d. Press the c/- key to turn Option Switch 07 on.
  • e. Press EXIT when you are finished.

Programming in Blast Mode

4. Place the locomotive on the main track (if it is not there already). If DCC track power is off, turn it on using the POWER key. Make sure that the locomotive to be programmed still runs on DCC using address three (or whatever other address you have programmed into it).

5. Keep pressing the PROG key until you see PAGE on the display. This sets the programming mode.

6. Press the LOCO key until you see AD4 on the display. This indicates the mode for setting a four digit address.

7. Use the keyboard to enter the four digit address that you want (e.g., 1234 or any other address between 128 and 9983).

8. When you have finished entering the four digit address, write the new address to your locomotive by pressing the CV-WR key. Do not be surprised if the locomotive moves forward one foot or more when the programming takes place. This movement doesn’t always happen, but it can.

9. To exit the Blast Mode or Programming on the Main mode, press the EXIT key.

10. To run the locomotive with the address you entered in Step 7, press the LOCO key; re-enter the address entered in Step 7 by using the keyboard; and press the LOCO key again.

11. Verify that the locomotive runs using its new address.

12. If the locomotive did not run in Step 11 when you used its new address:

  • a) Turn off DCC track power and move the locomotive that you are trying to program from the main line to the program track.
  • b) Use Direct Mode programming (or whatever type of programming your decoder requires) to read the values of CV29 and AD4. For a four digit address, the value of CV29 should be 38 (thirty eight) and AD4 should equal the address that you entered in Step 7.
  • c) If either or both of these values are incorrect, change them. You may make any necessary changes in Direct Mode while the locomotive is on the program track.

Turning of the Blast Mode

13. Turn off Blast Mode programming by changing Option Switch 07 to off.

a. Press the PROG key.

b. Press the SWITCH key.

c. Use the keyboard to enter 07.

d. Press the t/+ key to change Option Switch 07 to “off.”

e. Press the EXIT key when finished.

14. If your locomotive has a QSI sound decoder and you set CV62 to 0 (zero) in Step 2, put the locomotive back on the main line, run it briefly at its new 4-digit address, and configure the Zephyr or Zephyr Xtra for Operations Mode programming. Now change CV62 back to its default value of 1 (one).


JHM 11/9/2011.


For more info, see the Atlas website.