Inc Sound Module Decoder - Manual

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When speed table is enabled and 128 speed step information is received from

the command station, the table is interpolated to generate 4 in-between steps to

give full 128 step resolution.

28 Step Speed Table Programming Example

1. Program CVs 65 through 95 and CV29 with CV values from

TABLE VI.

2. After programming the table values, program CV29 to the value of 16

to enable the loadable speed table. If you want to disable the load-

able speed table later, just program CV29 to 06 and you will return

to 128 speed step operation (the speed table is still remembered and

can be re activated by programming CV29 to 16 again later). Setting

CV29 to the value of 16 will enable the 28/128 step speed table,

enable analog mode conversion, set the normal direction of travel

of the loco and enable 2 digit addressing. This CV value is just one

of many choices to enable the loadable speed table and control the

other variables handled by CV29 at the same time. Consult CV29

TABLE IV above for complete information about what value to pro-

gram into CV29 to get the features you want.

3. Once the speed table is programmed, you can scale the entire speed

curve by using the forward trim value (CV66) and reverse trim value

(CV95). These CVs act like a “volume control.” When you use

these trim values, you don’t have to reload the entire 28 step table if

you want to change, for example, the maximum forward speed from

45 scale mph to 80 scale mph. Changing the forward or reverse trim

values will scale all the values used in the table, in the correspond-

ing direction, by the value programmed into the CV. Using different

forward and reverse trim values allows for many different combina-

tions. The trim values can increase the table values from 100% up to

200% or decrease them from 100% down to 2%.

When speed matching locos, get the first loco running the way you like and

then match subsequent locos to it. We strongly recommend that you keep a

running list of the CVs and CV values you have programmed for each decoder.

When CV29 is set to enable a loadable speed table, any V-max(CV05) or

V-mid(CV06) values programmed are not used by the decoder when it deter-

mines how much motor voltage to apply. Non FX decoders don’t use V-start

(CV02) when a loadable speed table is enabled. Non-FX decoders don’t run

loadable speed tables in 128 speed step mode. To run non-FX decoders with a

loadable speed table, you must run them in 14 or 28 speed step mode. Set their

CV29 value to 016, 017, 020, 021, 048, 049, 052 or 053 and status edit these

decoders to a value of 10, 20, 12, or 22. FX decoders have start voltage and

128 speed step table operation available.