Zimo MX649N Remapping Issue

[Graham Radish]

The REAR light output function "yellow wire" on my Zimo MX649N decoder is damaged it stays on and will not go off (shorted) i have checked this to confirm, it is shorted.

 

Now as this is a 4 function sound decoder this leaves me with 3 lighting functions,

 

WHITE - Front Lights

GREEN -  Function Output 1

BROWN - Function Output 2

 

Obviously using my Digikeijs DR5000 the lightbulb/lights button now only switches on the front lights as the rear is now dead,  (actually the front and rear were tied together) therefore i would now like to map f01 and f02, (Green & Brown Wires) to the directional lights of the loco instead of the default setting, now i have no idea how to do this, basically i would like the "lights" button of my controller to select the lighting instead of pressing  the f8 function button.

 

I know how the wiring works but don't know how to remap, if anyone could help me out with this that would be great.

 

Cheers.

 

 

 

 

 

 

[jpendle]

Hi,

 

Your ability to rewire the decoder depends on the PCB in the loco.

On most N Gauge locos with a 6 pin socket the front and rear lights cannot be operated independently.

 

So you need to work out whether to use Function output 1 or 2 to replace the faulty wire.

 

Then we can help with Function mapping and how to make F1 or F 2 directional.

 

Regards,

 

John P

[Graham Radish]

Hello,

 

Theres no PCB in the loco, the decoder is hard wired to the lights, i desoldered the pins on purchase as there wasnt enough room to fit otherwise.

 

I originally tied the front and rear to one direction and the same for the other then pressing the controllers direction button swapped them around (pretty standard way) basically the stock setup, but then my (yellow wire) / rear function failed and now lights only work in one direction.

 

So now im left with 3 functions, i originally used f01 and f02 (green and brown) for cab lights, but now i cannot do that because the directionals arent working, so really i need to use fo1 (green wire) to be directional in tandem with the white wire.

 

 

 

 

Edited June 15, 2020 by Graham Radish

[JimFin]

7 hours ago, Graham Radish said:

Now as this is a 4 function sound decoder this leaves me with 3 lighting functions,

I think you may be missing a detail - F0 is the lighting function - controlled front and rear with the direction switch. You have used F1 and F2 for the cab lighting but are missing that F3 and F4 are still available to you. An option would be to use either of those to run the rear lighting as a substitute for the shorted yellow wire. You would need to solder a wire onto the appropriate pad on the decoder The diagram for this is on P12 of the attached.

MX-KleineDecoder_E.pdf

[Nigelcliffe]

31 minutes ago, JimFin said:

I think you may be missing a detail - F0 is the lighting function - controlled front and rear with the direction switch. You have used F1 and F2 for the cab lighting but are missing that F3 and F4 are still available to you. An option would be to use either of those to run the rear lighting as a substitute for the shorted yellow wire. You would need to solder a wire onto the appropriate pad on the decoder The diagram for this is on P12 of the attached.

MX-KleineDecoder_E.pdf 5.24 MB · 2 downloads

 

NO!    At least "No, don't just connect without some thinking"...  

 

The MX649 has four "normal" outputs and two "logic" outputs (Fo3, Fo4).   With suitable wiring components, they can be used, but they either need transistor switches adding (transistor plus resistor and then behave like a normal output), or can be used directly as very low current sources, but they switch to decoder ground (normal outputs switch from decoder positive).   

Its an option, I suspect can be used directly with a suitable resistor to the LEDs (lower value than full function output resistor), plus a route back to decoder ground.

 

 

Function remapping: 

Can do it in several ways.  The traditional is the mapping table (page 26).   With that, read across each line (note F0-key has two lines, one for forwards, one for reverse), and put a "tick" in each box required.  

So, to move the green wire (Fo1) to work on F0-reverse, a tick in the box in the second row.   
Add up the binary numbers from the right:  box1= 1,  box2 = 2, box3 = 4, box4= 8, box5=16...     Our tick is in box3, so set CV34=4.

To remove green wire (Fo1) from the F1-key, need to remove it from the default mapping. Third row of table, we see box3(=4) has a tick, which is currently mapping that output.  Set CV35=0 removes the tick from the line, and F1-key no longer works output Fo1.

 

 

- Nigel

[markw]

Another way to do it is to use Input Mapping, change CV400 to 59.

That will make the green wire operate as if it were a yellow wire.

[Graham Radish]

So knowledgeable here youre great!

 

" fo3 fo4 Its an option, I suspect can be used directly with a suitable resistor to the LEDs (lower value than full function output resistor), plus a route back to decoder ground"

 

Great so these could be used for cab lights? any idea what voltage they output?

Edited June 15, 2020 by Graham Radish

[Graham Radish]

7 hours ago, JimFin said:

I think you may be missing a detail - F0 is the lighting function - controlled front and rear with the direction switch. You have used F1 and F2 for the cab lighting but are missing that F3 and F4 are still available to you. An option would be to use either of those to run the rear lighting as a substitute for the shorted yellow wire. You would need to solder a wire onto the appropriate pad on the decoder The diagram for this is on P12 of the attached.

MX-KleineDecoder_E.pdf 5.24 MB · 5 downloads

 

This i did not know thanks very much.

[Graham Radish]

On 15/06/2020 at 10:25, Nigelcliffe said:

 

NO!    At least "No, don't just connect without some thinking"...  

 

The MX649 has four "normal" outputs and two "logic" outputs (Fo3, Fo4).   With suitable wiring components, they can be used, but they either need transistor switches adding (transistor plus resistor and then behave like a normal output), or can be used directly as very low current sources, but they switch to decoder ground (normal outputs switch from decoder positive).   

Its an option, I suspect can be used directly with a suitable resistor to the LEDs (lower value than full function output resistor), plus a route back to decoder ground.

 

 

Function remapping: 

Can do it in several ways.  The traditional is the mapping table (page 26).   With that, read across each line (note F0-key has two lines, one for forwards, one for reverse), and put a "tick" in each box required.  

So, to move the green wire (Fo1) to work on F0-reverse, a tick in the box in the second row.   
Add up the binary numbers from the right:  box1= 1,  box2 = 2, box3 = 4, box4= 8, box5=16...     Our tick is in box3, so set CV34=4.

To remove green wire (Fo1) from the F1-key, need to remove it from the default mapping. Third row of table, we see box3(=4) has a tick, which is currently mapping that output.  Set CV35=0 removes the tick from the line, and F1-key no longer works output Fo1.

 

 

- Nigel

 

Right, ive test installed a "cab light" (not installed in the loco yet)  with a 0406 SMT yellow LED and 470ohm resistor, the led is lit but its too dim, so i suspect a 270ohm resistor would be about right for the job or 2x470ohm resistors in series, as im going to be using the "servo" or "susi" outputs for cab lighting, how do i go about making them directional using 2xfunction keys (function key 20 and function key 21) ?

 

Thanks.

 

 

 

 

Edited June 24, 2020 by Graham Radish

[Nigelcliffe]

If using the logic outputs, you need to be careful on the maximum current flowing.  Its very low, somewhere around 10mA.   Some digging on Zimo website will be needed to find a recommended maximum value.  

 

 

For the CV changes, you need the Zimo manual, from their website, in English.

 

First, change the outputs of the Susi/Servo to Logic Level functions.  
Section, 3.25 SUSI-Interface and Logic-Level Outputs,  CV124, bit 7.

 

Then for function keys 20/21, you're going to need   Section 3.17 The "Swiss Mapping"  (whilst the manual talks about Swiss lighting combinations, its a lot more useful than that). 

You'll need to create two groups, one for F20, activating one of the outputs in the Forward direction, and one entry for F21 activating the other output in the reverse direction.

 

Group 1 -

The F-Key,  Set CV430=20 for function key 20.

Then the mapping Group 1, for A1 forwards,  CV432=3 for Function Output Fo3.

 

Group 2

The F-Key, Set CV436=21 for function key 21.

Then the mapping group 2, for A1 reverse direction, CV440=4 for Function Output Fo4.

 

 

 

 

[Graham Radish]

Amazing stuff nigel, im going to print this information on paper and get to work, yea will be a single 0402 led at either end, ill put a variable resistor in series with the led and adjust it to a suitable brightness then measure it to add the correct resistor, i didnt even know you could do this at all to be honest, but yea about 8ma per led as i suppose the good thing is cab lighting shouldnt be too bright anyway. 

 

Ive got the zimo cv list open on a pdf at the moment, i understand all the basics like speed limiting, but when it comes to stuff like this i get stuck lol!

 

anyway thank you very much this is a great help to me.

[Graham Radish]

2 hours ago, Nigelcliffe said:

If using the logic outputs, you need to be careful on the maximum current flowing.  Its very low, somewhere around 10mA.   Some digging on Zimo website will be needed to find a recommended maximum value.  

 

 

For the CV changes, you need the Zimo manual, from their website, in English.

 

First, change the outputs of the Susi/Servo to Logic Level functions.  
Section, 3.25 SUSI-Interface and Logic-Level Outputs,  CV124, bit 7.

 

Then for function keys 20/21, you're going to need   Section 3.17 The "Swiss Mapping"  (whilst the manual talks about Swiss lighting combinations, its a lot more useful than that). 

You'll need to create two groups, one for F20, activating one of the outputs in the Forward direction, and one entry for F21 activating the other output in the reverse direction.

 

Group 1 -

The F-Key,  Set CV430=20 for function key 20.

Then the mapping Group 1, for A1 forwards,  CV432=3 for Function Output Fo3.

 

Group 2

The F-Key, Set CV436=21 for function key 21.

Then the mapping group 2, for A1 reverse direction, CV440=4 for Function Output Fo4.

 

 

 

 

 

Ok this works brill! i couldnt get it working at first but once i changed cv432 to 5 instead of 3 it worked! same goes for changing cv440 to 6 instead of 4, dont know why lol.

 

anyway its all working now

 

Once i changed them from susi to logic outputs the 470ohm resistors i fitted were absolutely perfect in brightness!

 

and now the cab lights work independent of the front and tail lights - ive learned a lot from this thread awesome stuff indeed.

 

this is going straight in my model railway folder for future reference.

 

 

 

 

Edited June 24, 2020 by Graham Radish

[Nigelcliffe]

8 hours ago, Graham Radish said:

 

Ok this works brill! i couldnt get it working at first but once i changed cv432 to 5 instead of 3 it worked! same goes for changing cv440 to 6 instead of 4, dont know why lol.

 

 

Because I made a mistake.   5+6 is correct,  the outputs are numbers 5 and 6 for the logic level, whereas I'd put them on outputs 3 and 4 (which are real outputs). 

 

 

[Graham Radish]

8 hours ago, Nigelcliffe said:

 

Because I made a mistake.   5+6 is correct,  the outputs are numbers 5 and 6 for the logic level, whereas I'd put them on outputs 3 and 4 (which are real outputs). 

 

 

Im well chuffed with it hehe, although even my second farish class70 they are a swine to work on, due to them being so narrow, i think im gonna stick to class 37's in future maybe a 66, what i did for the speaker was take advantage of the fuel tank area, the whole of the fuel tank is a "back box" for the speaker sounds throaty now. sealed up with milliput black 2 part epoxy so its air tight. you could use "cotton bud tubing" as a bass reflex too

Edited June 25, 2020 by Graham Radish