OP
@isdeekelis avatar
UTC

Enthusiast
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
 
Enthusiast
@isdeekelis avatar
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
UTC quote
Hey,

Have created another small project. It is digital ignition advance angle display for scooters with CDI. It takes signal from pickup coil and signal from wire wound around spark plug wire, does the math and displays RPM and advance degrees. Has button to adjust pickup coil signal degrees BTDC.

Code: https://github.com/rverzinkevicius/ignition_advance

External inline image provided by member with no explanatory text
@ginch avatar
UTC

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
 
Veni, Vidi, Posti
@ginch avatar
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
UTC quote
Re: digital ignition advance display
isdeekelis wrote:
Hey,

Have created another small project. It is digital ignition advance angle display for scooters with CDI. It takes signal from pickup coil and signal from wire wound around spark plug wire, does the math and displays RPM and advance degrees. Has button to adjust pickup coil signal degrees BTDC.

Code: https://github.com/rverzinkevicius/ignition_advance
Looks very interesting. I guess this won't work on a 2 stroke Vespa with Ducati CDI?
@jkj-fz6 avatar
UTC

Ossessionato
BV400, Primavera 150, Yamaha Zuma 125
Joined: UTC
Posts: 4204
Location: Twin Cities, Minnesota
 
Ossessionato
@jkj-fz6 avatar
BV400, Primavera 150, Yamaha Zuma 125
Joined: UTC
Posts: 4204
Location: Twin Cities, Minnesota
UTC quote
Offhand, I don't see why it wouldn't work with some modifications to the software.

Interesting project!
UTC

Member
Joined: UTC
Posts: 5
Location: Philly 'Burbs
 
Member
Joined: UTC
Posts: 5
Location: Philly 'Burbs
UTC quote
Will it work on a 2 cylinder motor where both plugs fire simultaneously but the firing order is 360° out of phase (if that makes sense)?
OP
@isdeekelis avatar
UTC

Enthusiast
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
 
Enthusiast
@isdeekelis avatar
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
UTC quote
I think yes. There are few conditions for this to work: you need to have pickup coil and not contact ignition. You need to know how many degrees BTDC pickup generates signal. Also voltage of pickup coil should not be more than 3 volts in order not to damage esp8266.

Current code also has output for timing light, which requires 2n2222 transistor, 200 ohm resistor and LED. But i have noticed that advance mark is jumping few degrees at idle while checking with timing light and don't know why...
@ginch avatar
UTC

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
 
Veni, Vidi, Posti
@ginch avatar
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
UTC quote
isdeekelis wrote:
But i have noticed that advance mark is jumping few degrees at idle while checking with timing light and don't know why...
On your unit?
All I know is that using the Ducati type ignition (which is static rather than variable) you should set the ignition timing at around 3000 rpm on say, a PX. You'll see the timing move with the light on it lower than that... not a lot but enough to require setting at the higher speed.

External inline image provided by member with no explanatory text
External inline image provided by member with no explanatory text
OP
@isdeekelis avatar
UTC

Enthusiast
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
 
Enthusiast
@isdeekelis avatar
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
UTC quote
Same jumping both with usual timing light and timing light controlled by my unit.
I thought on usual timing light jumping is due to noise generated by coil/plug, so you first see light splash during spark and then several splashes afterwards generated by noise. I tried to eliminate this effect in code by ignoring subsequent voltage spikes after first one, but it looks like ignition is indeed jumping few degrees forth, but not back (retards, but not advances more than set).
Will check if signal from ecu sent to ignition coil is also jumping.

Anyway, i see correct advance degrees on screen and it doesn't jump and this was my goal.
OP
@isdeekelis avatar
UTC

Enthusiast
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
 
Enthusiast
@isdeekelis avatar
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
UTC quote
Although code handles noise, that noise is strong enough to trigger resistor which lights LED. Removing sensing wire from spark plug wire and simply holding it in hand (body works as antenna) eliminates jumping! So i need some circuit to reduce sensitivity.
OP
@isdeekelis avatar
UTC

Enthusiast
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
 
Enthusiast
@isdeekelis avatar
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
UTC quote
Success! Simple 0.01uF capacitor between spark sensing pin and GND solved it. Now mark is steady at idle.
Will try to draw schematic for whole this thing.

https://github.com/rverzinkevicius/ignition_advance/blob/master/tl.mp4?raw=true
@jkj-fz6 avatar
UTC

Ossessionato
BV400, Primavera 150, Yamaha Zuma 125
Joined: UTC
Posts: 4204
Location: Twin Cities, Minnesota
 
Ossessionato
@jkj-fz6 avatar
BV400, Primavera 150, Yamaha Zuma 125
Joined: UTC
Posts: 4204
Location: Twin Cities, Minnesota
UTC quote
I would add some transient suppression diodes to the spark and pickup inputs to protect the processor. There's nothing to limit voltage spikes from either source.

For example:
https://www.digikey.com/en/datasheets/littelfuseinc/littelfuse-inc-littelfuse_tvs_diode_sa_datasheet
OP
@isdeekelis avatar
UTC

Enthusiast
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
 
Enthusiast
@isdeekelis avatar
Derbi Boulevard 125 4t
Joined: UTC
Posts: 82
Location: Lithuania
UTC quote
Should be it:

External inline image provided by member with no explanatory text


By the way there is file "ignition_advance.bin" in github page. It is already compiled and there is no need to have Arduino IDE with all connected libraries. Just use https://github.com/nodemcu/nodemcu-flasher
⬆️    About 4 years elapsed    ⬇️
UTC

Lurker
Lml 151 4t
Joined: UTC
Posts: 1
Location: Italia
 
Lurker
Lml 151 4t
Joined: UTC
Posts: 1
Location: Italia
UTC quote
hi, I found this project very interesting, but when I try to compile it it gives me errors! would you give me help?
DoubleGood Design banner

Modern Vespa is the premier site for modern Vespa and Piaggio scooters. Vespa GTS300, GTS250, GTV, GT200, LX150, LXS, ET4, ET2, MP3, Fuoco, Elettrica and more.

Buy Me A Coffee
 

Shop on Amazon with Modern Vespa

Modern Vespa is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com


All Content Copyright 2005-2024 by Modern Vespa.
All Rights Reserved.


[ Time: 0.0393s ][ Queries: 3 (0.0113s) ][ Debug on ][ 313 ][ Thing One ]