ECM Modification Plots Readme
These plots where taken while modifing the ECM for the crank trigger and
the distributor number one detector.
The SDATA files are the binaries stored by the RMB Scope_dump program.
The Dump?.ps are the postscript output files.
Use the below to convert from the *.ps to a *.pdf
pstill -cR270 -o Dump20.pdf Dump20.ps
Plots 1 thru 19 .........
3312A Function generator settings:
12v pp, ground referenced
aprox. 16ms period (~9200 rpm)
Plots 20 thru 24 ........
Taken in the car
Note: The circuit's performance was independent of the input frequency (atleast
within the normal operation range of the motor.
sdata1 - R28 removed (no pull down)
- R22 = original 4.7k decoupling resistor
- Input = Function Generator
- #1 = 74HC14-4 Inverter Output
- #2 = 74HC14-3 Inverter Input
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
sdata2 - R28 removed (no pull down)
- R22 = original 4.7k decoupling resistor
- Input = Function Generator
- #1 = LM2904D-1 Output
- #2 = 74HC14-3 Inverter Input
- T1 = when the output of the op-amp hit zero
- T2 = when the inverter's output went high
sdata3 - R28 removed (no pull down)
- R22 = original 4.7k decoupling resistor
- Input = Function Generator
- #1 = LM2904D-1 Output
- #2 = LM2904D-2 Input
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
sdata4 - R28 = 562 ohms (total op-amp pull-down 892 ohms)
- R22 = original 4.7k decoupling resistor
- Input = Function Generator
- #1 = 74HC14-4 Inverter Output
- #2 = 74HC14-3 Inverter Input
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
- V1 = State change trip voltage
sdata5 - R28 = 562 ohms (total op-amp pull-down 892 ohms)
- R22 = original 4.7k decoupling resistor
- Input = Function Generator
- #1 = LM2904D-1 Output
- #2 = 74HC14-3 Inverter Input
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
- V1 = State change trip voltage
sdata6 - R28 = 562 ohms (total op-amp pull-down 892 ohms)
- R22 = original 4.7k decoupling resistor
- Input = Function Generator
- #1 = LM2904D-2 Input
- #2 = LM2904D-1 Output
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
- V1 = State change trip voltage
sdata7 - Input overshoot with clamping diode installed
- Input = Function Generator
- #2 = LM2904D-2 Input
sdata8 - R28 = 562 ohms (total op-amp pull-down 892 ohms)
- R22 = 562 ohms (de-coupling resistor)
- Input = Function Generator
- #1 = 74HC14-3 Inverter Input
- #2 = LM2904D-1 Output
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
- V1 = State change trip voltage
sdata9 - R28 = 562 ohms (total op-amp pull-down 892 ohms)
- R22 = 562 ohms (de-coupling resistor)
- Input = Function Generator
- #1 = Trigger input edge (J1-23)
- #2 = 74HC14-4 Inverter Output
- T1 = when the trigger edge arrived at the input (J1-23)
- T2 = when the inverter's output went high
- Total propagation time from input edge to inverter edge
sdata10 - R28 = 562 ohms (total op-amp pull-down 892 ohms)
- R22 = 562 ohms (de-coupling resistor)
- Input = Function Generator
- #1 = Trigger input Falling edge (J1-23)
- #2 = 74HC14-4 Inverter Output - Falling edge
- T1 = when the trigger falling edge arrived at the input (J1-23)
- T2 = when the inverter's output went low
- Total falling edge propagation time from input edge to inverter edge
sdata11 - Total propagation delay of the #1 detector circuit
- #1 = Trigger input edge (J1-4)
- #2 = 74HC14-2 Inverter Output
- T1 = when the trigger edge arrived at the input (J1-4)
- T2 = when the inverter's output went high
sdata12 - Hall effect trigger
- Vcc = 14 volts
- No cable. Scope at unloaded trigger 'Point' output
- T1 = trigger rising edge
- T2 = when the output voltage reached maximum
- V2 = maximum output voltage
sdata13 - Hall effect trigger
- Vcc = 14 volts
- No cable. Scope at unloaded trigger 'Point' output
- Scope calculated rise time: 1.17us
sdata14 - Hall effect trigger
- Vcc = 14 volts
- 12' supplied cable with Mag line still hooked up
- Scope calculated rise time: 5.07us
sdata15 - Hall effect trigger
- Vcc = 14 volts
- 12' supplied cable with Mag line still hooked up
- T1 = trigger rising edge
- T2 = when the output voltage reached maximum
- V2 = maximum output voltage
sdata16 - Hall effect trigger
- Vcc = 14 volts
- 12' supplied cable with Mag line dis-connected at weather-pack plug
- Scope calculated rise time: 3.5us
sdata17 - Hall effect trigger
- Vcc = 14 volts
- 12' supplied cable with Mag line dis-connected at weather-pack plug
- Attached to ECM input (J1-23)
- Rise time calculated at same V2 as sdata16: 7.44us
sdata18 - Hall effect trigger
- Vcc = 14 volts
- 12' supplied cable with Mag line dis-connected at weather-pack plug
- Attached to ECM input (J1-23)
- #1 = trigger input (J1-23)
- #2 = LM2904D-2 Input
- T2 = when LM2904-1 Output reacted to the input signal
- V2 = LM2904D-3 non-inverting input - hysteresis trip voltage
sdata19 - Hall effect trigger
- Vcc = 14 volts
- 12' supplied cable with Mag line dis-connected at weather-pack plug
- Attached to ECM input (J1-23)
- #1 = trigger input (J1-23)
- #2 = LM2904D-1 Output
- #3 = 74HC14-4 Output
- Delta T - Total propagation time from start of trigger to 74HC14 react
-------------------------------------------------------------------------------
These were taken in the car verifying crank trigger performance.
sdata20 - Crank Trigger Duty Cycle
- #1 = trigger input (J1-23)
- #2 = 74HC14-3 Inverter Input
- Delta T - Width of Crank Trigger Output Pulse
sdata21 - Propagation Delay
- #1 = trigger input (J1-23)
- #2 = 74HC14-3 Inverter Input
- T1 = crank trigger rising edge
- T2 = level where output of the inverter changes state
- Delta T = Propagation Delay
sdata22 - Distributor CAM position pickup (Idling about 850 RPM)
- #1 = 74HC14-1 CAM position inverter input
- #2 = 74HC14-3 Crank Trigger inverter input
- T1 = leading edge from the CAM position sensor
- T2 = leading edge from the crank trigger
- Idling around 850 RPM
sdata23 - Distributor CAM position pickup (about 1700 RPM)
- #1 = 74HC14-1 CAM position inverter input
- #2 = 74HC14-3 Crank Trigger inverter input
- T1 = #2 firing edge
- T2 = #1 firing edge
- 1700 RPM
sdata24 - Distributor CAM position pickup (about 4300 RPM)
- #1 = 74HC14-1 CAM position inverter input
- #2 = 74HC14-3 Crank Trigger inverter input
- T1 = crank trigger firing edge
- T2 = CAM position pickup trailing edge
- 4300 rpm