Decoder CV Definitions

The NMRA Standard Definitions for Mobile Decoders

CV	Name	Value	Read Only
1	Primary Address (2 digit)	1-127	No
2	Minimum starting voltage	0-255	No
3	Acceleration Rate	0-255	No
4	Deceleration Rate	0-255	No
5	Maximum speed	0-255	No
6	Middle speed Vmid	0-255	No
7	Version Number	-	Yes
8	Manufacturer’s ID	-	Yes
9	Repeat Rate	0-63	No
10	EMF Feedback Cutout - Sets the speed step above which back EMF is no longer applied.	0-255	No
11	Packet Time-Out Value - Sets the maximum time that the decoder will maintain speed without receiving a valid data packet from the command station.	0-255	No
12	Power Source Conversion. Determines the secondary power source for the decoder.	0-255	No
13	Analogue Mode Function Status - Selectively sets decoder functions 1-8 to operate in analogue mode	0-255	No
14-16	Reserved for future development	0-255	No
17-18	Extended Address (4 digit - optional)	0-255	No
19	Consist Address (2 digit)	1-99	No
20	Reserved for future development	0-255	No
21	Consist Address Active for Functions 1 to Functions 8 - Sets whether Functions 1 to Functions 8 respond to commands at Consist Address in addition to the locomotive address.	0-255	No
22	Consist Address Active - Sets whether Function 0 (headlight control) responds directionally to commands at Consist Address	0-255	No
23	Fine Acceleration Adjustment	0-255	No
24	Fine Deceleration Adjustment	0-255	No
25	Speed Table/Mid-range - Allows selection of factory set speed tables and throttle position for the middle of the speed table	0-255	No
26-27	Reserved for future development	0-255	No
28	RailCom configuration	-	No
29	Settings for : Direction of travel, Speed Steps, DCC running only or DCC & DC, RailCom enabled or disabled, Preset Speed Curve or consumer defined, Preset Speed Curve or consumer defined, Basic address or extended address	-	No
30	Error or fault display	-	No
31	Configuration Data #2 (reserved for future development)	0	No
32	Configuration Data #3 (reserved for future development)	0	No
33	Function 0 (forward headlight)	0-255	No
34	Function 0 (reverse headlight)	0-255	No
35	Function 1	0-255	No
36	Function 2	0-255	No
37	Function 3	0-255	No
38	Function 4	0-255	No
39	Function 5	0-255	No
40	Function 6	0-255	No
41	Function 7	0-255	No
42	Function 8	0-255	No
43	Function 9	0-255	No
44	Function 10	0-255	No
45	Function 11	0-255	No
46	Function 12	0-255	No
47-48	Reserved for future development	-	No
49	Reserved for future manufacturer’s development.	-	No
50	Motor configuration	-	No
51	Braking configuration	-	No
52	Braking distance with activated constant braking distance	0-255	No
53	Slow approach	0-255	No
54	Stopping time in push pull operation	0-255	No
55	Sets brightness at function outputs A & B	0-255	No
56	Sets brightness at function outputs B & D	0-255	No
57	Dimming	0-255	No
58	Shunting speed	0-255	No
59	Switching off the delay	0-255	No
60	Lighting effect at function outputs A & B	0-255	No
61	Function mapping; lighting effect at function outputs A & B	0-255	No
62	Lighting effect at function outputs C & D	0-255	No
63	Flashing frequency for function outputs C & D	-	No
64	Function mapping; lighting effect at function outputs C & D	-	No
65	Power surge - Extra surge between speed steps 0 and 1 to help start “difficult” motors	0-255	No
66	Forward Trim adjustment	128	No
67-94	Speed Curve Values	0-255	No
95	Reverse Trim (optional) - Lower value to reduce reverse speed, raise value to increase reverse speed. 0=off.	128	No
96-104	Reserved for future development	-	No
105	Reserved for customer use #1	0-255	No
106	Reserved for customer use #2	0-255	No
107-111	Reserved for future development	0-255	No
112	Duration of motor timeout when track signal has ceased.	-	No
113	Minimum PWM value.	-	No
114	Motor change duty cycle	-	No
115 - 125	Reserved for future development	0-255	No
126	CV (indicator) for S.U.S.I	0-255	No
127	CV (transport device) for S.U.S.I	-	No
128	Service number	0-255	No
129- 512	Reserved for future expansion	0-255	No

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