JMRI: DS54 Examples

Examples of using a Digitrax DS54 with JMRI.

The DS54 accessory decoder can be configured in a large number of ways. (DecoderPro can help with that)

Walter Thompson walked through the details of this:

With the ds54 at defaults these are the Loconet msgs when either Switch A or Aux A goes positive causing the Turnout to "toggle" state:
When Switch A (blue lead) goes high loconet msg [b2 8 70 35].
When Aux A (orange lead) goes high loconet msg [b2 8 50 15]

I then set "When Switch A input changes, send" ="Turnout feedback msg"
When Switch A (blue lead) goes high loconet msg [b2 8 70 36]
When Aux A (orange lead) goes high loconet msg [b2 8 50 15]

I then set "When Aux A input changes, send"= "Turnout feedback message"
When Switch A (blue lead) goes high loconet msg [b2 8 70 36]
When Aux A (orange lead) goes high loconet msg [b2 8 50 16]

Therefore, when the Switch and Aux inputs are set to send a turnout feedback message, the feedback mechanisms built into recent versions of JMRI can be used to track the turnout state when the local inputs are used to change the turnout.

Exact Feedback

To use exact feedback, you need to connect two microswitches to the turnout and to the Switch and Aux inputs on the DS54. (You can use the built in Tortoise contacts for this)

Configure the DS54 channel with:

 Aux A input"='Active ON, trigger on change, Postive Level"
 Aux A task"="No Output change"
 When Aux A input changes, send"= "Exact turnout feedback message"
 Switch A input"='Active ON, trigger on change, Postive Level"
 Switch A task"="No Output change"
 Switch A input changes, send"= "Exact turnout feedback message"

Configure Turnout LT9 (via the Turnout Table) to use "EXACT" feedback.

Commentary	Loconet messages
Start with Turnout 9 closed Switch A will be Closed and Aux A open.	none

Issue a "Throw Turnout 9" command from the throttle or the turnout table	`[b0 8 10 57]` Requesting Switch at 9 to Thrown (output On) `[b0 8 0 47]` Requesting Switch at 9 to Thrown (output Off)
Turnout starts to move and opens Switch A	`[b1 8 60 26]` Turnout 9 Switch input is Thrown (input on)
Moving turnout closes Aux A and reaches the end of its travel.	`[b1 8 50 16]` Turnout 9 Aux input is Closed (input off)

Now issue a "Close Turnout 9" command	`[b0 8 30 77]` Requesting Switch at 9 to Closed (output On) `[b0 8 20 67]` Requesting Switch at 9 to Closed (output Off)
Turnout starts to move, opens Aux A	`[b1 8 40 6]` Turnout 9 Aux input is Thrown (input on)
Moving turnout closes Switch A and reaches the end of its travel.	`[b1 8 70 36]` Turnout 9 Switch input is Closed (input off)