28 Speed Step DCC Decoders

[bcjim]

Some of the older Bachmann units like the SD-45 GP-35 that are
DCC on board show 28 speed steps written on the box.
No mention if this will only support 2 digit address
or if one can program a 4 digit address on a 28 speed step unit.
Is this limited to a 2 digit address?
Thanks, Jim

[bcjim]

Thank you for getting back to me.
The GP-35 unit is at the hobby shop.
We did not want to buy it until we know it will do 4 digits 128 speed step.
Since it just said 28 speed steps, we were Leary.
I have used and am happy with the 36-552 decoder  but have no idea if that
is  in the GP-35.
I don't think the follow at the hobby shop would be to happy about me taking the unit apart to see.
I have a Digitrax PR-3 programmer and have not had any  problems
programming  Bachmann decoders so far.
Jim.