Smart-Round-Dual was the
The manufactured version:
Features:
- 3 digit 7 segment LED (with dots)
- 4 digit 7 segment LED (with dots)
- Voltage output. High resolution (up to 5V, 12bit, programmable output curve)
- RS232 level
- directly plugs into PC
- or USB-RS232 adapter
- or small dongle for CAN-physical layer bus (will not need to be removed from network even for firmware reflash!)
- free outputs
- power
- signal level (0..5V high resolution, external ground referenced)
- extra inputs
- analog input
- RPM input (or vehicle-speed)
- button
Firmware features
Since this is ment as an easy-to-use device, first only very few features are supported.
- WBO2. Lambda value matches Bosch (manufacturer of the LSU4 sensor) specifications. Tested against very expensive 6-gas analyzers (with 2 sensors in same exhaust stream) with very good match (showing 0.86 / 0.87 when the high-end analyzer displayed 0.86 lambda)
- EGT (with cold-junction measurement)
- soon: null-offset calibration
- onboard-temp
- Data can be logged to PC for further analysis
Some pins suggest boostcontrol function. Note that (although possible, the hardware supports it at the same time as WBO2 and EGT) there is no boostcontrol firmware code for it now.
RPM input (VR or HALL, several trigger-types) will be supported in firmware later (currently not), eg.
RPM is scheduled to be available in firmware in 2..3 months. I recommend to wait if you don't need the unit right now and know you'll need RPM ( though it should be a firmware-only change, the input voltage levels will be calibrated later in production making it easier to use )
- for logging
- or (RPM-dependent) boost-target
- or vehicle-speed sensor data can be sent over the network to GenBoard/VerThree even when both primary and secondary VR inputs of the v3.x are used up for the engine (the vehicle-speed and fuel consumption can be displayed and logged; also allows much better street-dyno implementation than without vehicle-speed)
Pinout
RS232 (standard DSUB9 female, pin2,3,5)
- RX
- TX
- GND
Main connector - DSUB15 male. Note that the (now standard) flying loom version has the WBO2 pins on the WBO2 connector, so those 5 pins (pin 2,3,4,5 and 7) of the DSUB15 are NOT connected:
- 1: Vout (voltage output signal +)
- 2: WBO2 pump- (Sensor pin 5)
- 3: WBO2 nernst (Sensor pin 1)
- 4: WBO2 pump+ (Sensor pin 6)
- 5: WBO2 Rcal (Sensor pin 2)
- 6: VBatt+ (12V)
- 7: WBO2 heater-(Sensor pin 4)
- 8: analog input
- 9: Vout-gndref (voltage output signal) -. Connect to GND or max 2..5V potential (with higher voltage on this pin, max output voltage on Vout will be limited).
- 10: RPM input
- 11: RPM reference (input threshold can be adjusted; leave open)
- 12: boost solenoid output (or other power output) max 5A, flyback towards supply
- 13: GND connect all GND-s
- 14: GND connect all GND-s
- 15: GND connect all GND-s
- Also wire supply voltage to WBO2 Heater to sensor pin 3 through 5A fuse (this is wired this way in the supplied harness)
Mounting
The flying loom version allows mounting even with the tightest available space:
The upcoming mounting style uses an U bracket:
This really is a professional product, now we need to get the marketing name right...
OLD stuff ... TODO: cleanup
The AfreshTiny was the working name for our first round 52mm WBo2 meter design.
Same circuit can also be used for other functions, see AfreshTiny/OtherUses
Input from user
- How do we trigger the free air calibration? At all? (would be nice)
- How do we choose between Lambda and AFR display? (or Celsius/Fahrenheit)
- How do we choose vout curve?
- How to insert "markpoints" in the datalog
Because of the
- analog inputs
- button
- network connection
this is a software issue.
Which ones do we need ? HW output (high vout resolution) allows either:
Linear WBO2 lambda output
Useful with ECU-s that has no embedded WBO2 controller, but can accept linear WBO2 signal! Also useful if the other ECU has real WBO2 input but you don't want to use 2 WBO2 sensor.
This was tried with 3V/lambda wired in (connected to a motec). Included in next release in a configurable way (so either NBO2, or linear output can be selected with chosen n V / lambda ).
0V (well, say < 0.2V) used for unknown (eg. sensor not heated yet)
- 1V / lambda 0.65v@lambda=0.65, 1.5v@Lambda=1.5
- only when this is the only choice; or when viewing with a handheld DVM
- 3V / lambda was successfully tried with motec input. The input curve in Motec can be configured (allows 0..5V input range)
- 4V / lambda : maximum practical (max 1.25 lambda limited by output range)
- 5V / lambda could be useful with -1.5V offset (0.6 lambda => 1.5 V ; 1.3 lambda => 5V). This would allow the best interfacing precision (although 3V / lambda is already very good).
NBO2 - implemented
- NB sensor simulator, LSM11 reference curve. This curve is mostly useful for old type NBO2 input equipped factory ECU-s only, since it has very low slope (=> hard to tune, prone to noise) at lambda=0.8 which is kindof unfortunate
Special
- Autronic standard, 0-1v= AFR10-30
- using the near 0V part of the curve is very unfortunate (much better is 0V = error or unknown)
- 10 AFR (0.68 lambda) minimum is a bit unfortunate as well
- old diy style 0..5V: 2.08V best power, 2.5V stoich. (this is Ip based, was implemented at one point, easy to get back if needed)
- Linear 0-5V EGT output (5V = 1200C or so?). It could be also good usable with other ECU-s that can't accept the k-thermocouple signal directly.
Note: besides the vout curve, the vout filter frequency would be nice if adjustable (when using it with other aftermarket systems, sometimes you want it almost unfiltered and sometimes you want it as slow as 1Hz.)