[ARCHIVE] This version is discontinued.
Consider to build v7 instead!

Characteristics.

• Adaptable to other single-cylinder bikes.
• High precision (0.07 degree).
• Preprogrammed for XT400/550/2strokes (84 or 106 points).
• Software source unavailable (only .HEX).
• Need a working charging coil for the capacitor.
• Need a battery

DOWNLOAD

How does it works?

The part CDI (Capacitive Discharge Ignition) is described in the page “fixed ignition“.

Use of a 16f628 (cheaper and better than the 16f84).
No more crystal, internal 4MHz clock instead, no more connector.
Much more accurate and steady than v5.4.

Let us see this in details…

Pulses coming from the 12° pickup directly trigger the SCR via D7 R7 C10. This pulse doesn’t go through the PIC.

At the same time, pulses coming from the 36° pickup are limited to 5 volts by the Zener D9 then trigger the PIC (RB4 – pin 10).
(PIC input detect any tension higher than 1,8 Volts.)

The green LED D1 come on at each correct pulse received from sensor 36°.

A delayed pulse, according to the programmed advance curve, is available on pin 8 (RB2) and trigger the SCR T1 via D2,R7,C10.

If your bike have only one pulsar (pickup), connect it to the 36° input and leave the 12° input unconnected.
The polarity of the pickup is important, don’t hesitate to invert the 2 wires of the pickup.

Ways of the 12 and 36deg signals:

There are 2 sparks by revolution:one before the TDC (from the 36deg pickup) and another at TDC (from the 12deg pickup – if connected) This second spark is useless. (wasted spark)

On animation below, one can see the signal from the pickup (white trace, PIC input pin10) and the signal for the SCR (pink, PIC output, between D2 and R7) at various speeds between 1300rpm to 6000rpm

We can see:
– At low rpm: the output signal is provided a little time after the input signal, therefore at the TDC.
-At high rpm: the output signal is provided at the same time as the pickup signal, therefore before the TDC.

Max Ignition Frequency 400Hz.

The software can reach 730Hz but SCR is limiting to 400Hz.

Warning! If there is one spark lose, the max rpm is divided by 2

IE: 400Hz = 44000 RPM when only ONE spark by rotation or 22000 RPM if TWO sparks by rotation (one spark is wasted)

Main functions of the software

Easy kickstart
Advance is set for a easy kickstart at 300rpm.

Coil protection
Coil is never on while the engine is stopped.

RPM Limitation: (optional)
Over 10.900 RPM for the 2strokes version or 6510rpm for XT400, ignition is stopped, no more sparks. This limitation can be removed (JP2).

Advance calculation:
Between the maximum and the minimum RPM, the PIC measure the duration between 2 pick up pulses [the number of 4us (four microsecondes) periods between two pulses] to deduce the speed of the engine.
According to the revs, the PIC is calculating the position in the map.

Duration of the spark:
The duration of the spark cannot be adjust on a CDI, it depend of the capacitor value and the coil value.
The duration while the thyristor is on to discharge the capacitor, is set to 1ms (one milli second)

Accuracy:
The curve is defined by 80 to 106 points. The accuracy is high: 0.07 degree.

Modification:
The source code is not available and the software is disued. Please consider V7 instead.

LEDs:
– At startup, Led D1 blinks 4times if map1 is selected, and 3times if map2 is selected.
– When pickup input pin10 is high [>2.4v], D1 led is on
So at each pulse received from the pickup, LED D1 blink.
  If LED D1 stay on, that mean pin10 is always high!
Measure pin10 and try to lower R9 value from 470Kohm to 1.8Kohm or less…

– You can remove D1 + R6 to lower the current consumption.
– At each pulse from the PIC (output pin8) going to the SCR, LED D2 blink.
– D2 is a High sensibility LED
– You can replace D2 by a 1N4148 if you don’t like blinking led.

Jumpers:
JP1: no jumper => use first curve (map1), jumper ON => use second curve (map2).
JP2: no jumper => no RPM limitation, jumper ON => RPM limitation.

Software.

v6.4 (works with v6.6 hardware. jumper JP1 ON = map1)	Source .HEX (ASM unavailable)
PIC 16F628 for XT400-550(1953-6510rpm)
PIC 16F628 for DR800(1723-6510rpm)
PIC 16F628 for 2 strokes(3170-10900rpm)
PIC 16F628 for 2 strokes(3446-13020rpm)
PIC 16F628A for DTLC125 57U – 1987(1386-10200rpm)
PIC 16F628A for karting Zanella 125cc(2083-15625rpm)
PIC 16F628A for Honda Cub 110cc(989-13021rpm)
PIC 16F628A for a 2 strokes RC model engine(1023-9014rpm)
PIC 16F628A for a 4 strokes scooter(1023-9014rpm)
PIC 16F628A for Honda CM400(977-15625rpm)

v6.5 (works with v6.6 hardware. jumper JP1 ON = map1)	Source .HEX (Source code .ASM unavailable)
PIC 16F628A for Honda S50(989-11719rpm)
PIC 16F628A for XT400-550(1037-8082rpm)
PIC 16F628A for FML163 Chinese 200cc(1005-10653rpm)
PIC 16f628A for Yamaha XT200(1037-8081rpm)

v6.7	Source .HEX (ASM unavailable)
PIC 16F628A for scooter 50cc Honda Lead AF20(989-11719rpm)
PIC 16F628A for Honda Cup 110cc(988-13040rpm)
PIC 16F628A for FML163 Chinese 200cc 4 strokes2 maps (919-11718rpm)

Printed Circuit Board.

Warning: PCB for version 6 is different than the one for v7 !

Compatibility with others pickups.

Starting from v6.5, PCB has been modified in order to be triggered either by a positive-first pickup signal or a negative-first signal. Just use and weld the appropriate components:

For positive-first pickup signal
Yamaha, Kawasaki
	Remove: Q1, Q2, R10, R11 Add : D4, D9, R9, C3

For negative-first pickup signal
Honda, Suzuki
	Remove: D4, D9, R9, C3 Add : Q1, Q2, R10, R11

Tests.

• Remove the PIC16F628 of its support.
• Take out the spark plug from the engine and connect it to the spark plug wire.
• Ground the metal part of the spark plug to the bike’s frame by touching a good metal part.
• Hook up the CDI to the alternator and to the spark coil
  (Don’t connect neither the +12v, nor the sensor, nor the kill switch)
• Kick start several times to charge the big C11 condensator.
• Measure the tension between Anode and Kathode of thyristor T1. You must read around 150Vdc. (the tension slowly decreases because the condensator is discharging into the multimeter…)
  
• Wait 30sec, measure again: the tension should not drop while the multimetre is disconnect.
• Kick start several times to reload the big C11 condensator.
• Touch the 12deg input with a wire connected to the +12v battery to trigger the SCR.
• You’ll see a spark at the spark plug.
• Connect all the wires from the pickup.
  (But don’t connect the +12v and don’t connect the kill switch)
• Kickstart, the 12deg pickup pull out a pulse each turn, this pulse trigger the SCR T1 through D7, R7, C10 and produce a spark.
• Insert the PIC16F628 in its support, in the good position! Plug in the +12v power.
• Since V6.5, test LED is blinking 4 times at startup, meaning that PIC+programmation+software are OK.
• Screw the spark plug on the engine,ensure everything is hoocked up (ground, +12volts, alternator, pickup, spark coil, spark plug) and start the engine
• You can test the CDI with my Pickup Simulator

Videos.

Versions.