Diagnostics D Command

There are a number of diagnostic facilities under the <D> command, most are harmless but caution is advised.

The <D> commands are intended for diagnostics only which means that their behaviour can change from one release to another without warning

These commands can be entered directly via the USB serial console or through a Wifi connection to the command station with a tool such as Telnet or Putty. JMRI includes the DCC++ traffic monitor which lets you insert DCC++ serial commands as well. (links required)

<D CABS> Lists the locomotives which the command station is currently managing.

<D RAM> Displays the free RAM on your Arduino.

<D RESET> Resets the Command Station

The following commands turn ON(1) or OFF(0) various diagnostic traces

<D ACK ON|OFF> trace DCC ACK processing when reading/writing on the prog track. Diagnostics D ACK Command

<D CMD ON|OFF> trace received JMRI commands.

<D WIFI ON|OFF> trace Wifi protocol AT command conversation between Arduino and Wifi hardware.

<D ETHERNET ON|OFF> trace Ethernet conversation between Arduino and Ethernet hardware.

<D WIT ON|OFF> trace WiThrottle protocol conversation of Engine Driver (or other WiThrottle device).

The following command might help in exceptional circumstances

<D PROGBOOST> When the programming track is switched on with <1> or <1 PROG> it will normally be restricted to 250mA according to NMRA standards. Some loco decoders require more than this, especially sound versions. <D PROGBOOST> temporarily removes this limit to allow the decoder more power. The normal limit will be re-imposed when the programming track is switched off with <0> or <0 PROG>.