Decoder R8249 general description…

The R8249
4 function decoder replaces the earlier R8215 4 function decoder.

The R8249 decoder
is similar to the R8215 in that it has the same hardware design. The major change
is in firmware. The decoder has enhanced functionality over its predecessor.
The decoder can be identified by the blue dot painted on its MCU.

The R8249 decoder is NMRA warranted.

..

The R8249 supports the following CVs..

CV1..

Loco
Address        Default
is 3   Long/short addressing supported

CV3..

Acceleration
Default is 5
Range 0-255

CV4..

Deceleration
Default is 5
Range 0-255

CV7..

Version
Number

CV8..

Manufacturer’s
ID = 48  (writing the value 8
to this CV resets decoder to default.)

CV10..

Back
EMF response.

Range
1-128 that indicates the speed step above which back EMF control cuts OFF. Default is 128.

CV17/18..

Used
for setting up long address.

CV29..

Default Decadic value = “6” (bit7 is ignored.)

Note: this may show as “134” on some
controllers’ due to reading bit 7 which is set to on in the factory.

The following bits are supported..

Bit0.. Default Direction..  (default is 0... normal)

Bit1.. Location of F0 Headlight/Rear light direction Control
bit

(default is 1... which corresponds to 128 speed steps operation.)

Bit2.. DC/DCC mode disable enable (default
is 1... power conversion on)

Bit5.. Long/Short Address set up. (one
or two byte address modes.

(default is 0... decoder address 03)

Bit6.. (fixed default is 0) not
used

Bit7.. (fixed default is 1) not
used

Full interrogation in.. Direct, Paged, Register and Operate programming mode is
supported.

..

Current Capability..

Motor
Output.. 500mA Continuous, 1A peak
for very short durations.

Function
Outputs.. 100mA each  x4

Note
the total current capability of the decoder is 500mA continuous shared between
all outputs.

Please note… When the R8249 became
available it took over from the older R8215 decoders. Hornby DCC fitted locos
now have this decoder in 4 pin inline connector configuration. The decoder will
also be used in Pendolino type locos.. I.e. those
locos fitted with two decoders.. i.e.
one in the “dummy” car in order to control the lights.

R8249/R8215
decoders are available in a total of 3 variations... i.e. The 4 pin inline
connector as discussed above, the standard 8 pin NMRA plug version and; a third
configuration which is unique to the Pendolino; in that it uses a 7 pin inline
connector.