AFreshTiny
Formerly known as Smart-Round-Dual, 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
- AfreshTiny/FirmwareUpgrade
- AfreshTiny/DisableAim
- AfreshTiny/VoltageOutput
- AfreshTiny/WidebandCalibration
- AfreshTiny/AnalogInput
- AfreshTiny/EgtCalibration
- AfreshTiny/RpmInput
- AfreshTiny/DemoRound (display constant text, eg. shop window)
- AfreshTiny/AimDisplay (v3.x => RS232 => round displays runtime data )
New features supported since 2010-03-29 firmware
- boostcontrol
- multiple RPM bins for boosttarget
- multiple RPM bins for boost reference PWM (refdc)
- These adjustable RPM bins provide fine control. (Note: in v3.x, (RPM,gear) can be used for even finer control)
- idlecontrol
- and producergas/woodgas mixture lambdacontrol (for engines that run on wood/waste)
- the air-mixing valve can be a 2-wire VW / Audi (VAG) PWM idle-PWM solenoid. Avoid the bigger "limphome" model that is open at 0%, closes most at 25%, and opens again from 25..100%
Related Software
- MegaTune
- Will be replaced by VemsTune
- Latest releases : http://www.vems.hu/download/round/
- log data the same way as with v3.x (megatune -> File -> Datalog)
- log analysis: vemslog viewer (or any LogAnalysis program that can take xls input)
- VemsTune
- Latest test releases : http://www.vems.hu/download/VemsTune/
- Very useful for firmware upgrades (and general use)
Documentation
Warning: the WBO2 sensor in the exhaust is ruined quickly if not heated. When the engine is running, keep the controller running too (so it keeps the sensor heated) or remove the sensor from the exhaust (and use a M18x1.5 mm plug).
- A more user friendly guide is found here: http://vems.hu/www.vems.co.uk/VEMSWB/UserGuide/README.html
- Round warning paper with WBO2 wire colors: http://vems.hu/download/round/docs/Round_pins1.doc
- We supply this printed paper with each round. This allows customers to push in the 6 WBO2 receptacles in the connector housing correctly (several customers asked that the WBO2 pins are not inserted in the connector housing during manufacturing, so they can pull through the firewall).
- The WBO2 pin 5 (pump-) wire is either transparent or thin brown (see the paper). The thicker brown wire is still the heater.
Mounting
Allows mounting even with the tightest available space:
U-bracket mounting bracket:
The simple factory "harness" (with the DSUB15 female) only has supply wires and a fuse:
- +12V must be connected to the fuses (the wideband sensor internal heater consumes max 3A). Red wire on the picture.
- GND must be connected to the DSUB15 connector (blue wire on the picture)
- if you need special functions, like analog output, you need to open the DSUB15 and solder wire to the chosen pin (see pinout below)
- the EGT has a green cable with green (+) and white(-) wires: 25C/mV (=40uV/C in other words) sensitivity (offset and gain calibration capability in software): 0..48mV DC input for 0..1200C (+cold junction temperature must be added, that is inside the round case, normally appr 30C) and WBO2 use separate cables):
To connect for the WBO2 and EGT functionality is trivial (including datalogging with PC). The RPM input and voltage output has some options, detailed below (these functions are rarely used, but sometimes very useful).
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 (kmh / mph) or other frequency signal
- button
Firmware features
Since this is meant 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 - different - 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)
- null-offset calibration (egt_cal, mttg01mttc.. where replace .. with hexa number: C0 is default, 00 is maximum subtracted offset, 96C)
- onboard-temp
- Data can be logged to PC for further analysis
- Self-calibrating (no setup required, just plug and play)
RPM input (VR or HALL, several trigger-types)
- 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)
Free air calibration
The RCal resistor in the sensor is supported, so calibration is not necessary. The optimal PID parameters are different in the exhaust stream and free air, so don't worry if free air reading is slightly off or even floating somewhat. Note that toleration in the lamdba range is very good: 5% error means (actual => reading) 0.8 => 0.81 lambda (since the difference from lambda=1.0 counts, which is 0.2 and 0.19 respectively).
Connector Pinouts
RS232 - DSUB9 female. Note that any extension cable needs to be straight through and not cross-over.
- 2: RX
- 3: TX
- 5: 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 (Lambda output signal +) - configurable as either Narrow band, wideband 0-1v through to 0-5v.
- 6: VBatt+ (12V)
- 8: analog input for conditioned signal or NTC-type temperature sensor. The input has internal pullup to 4V. As a side-effect, an unconditioned signal (TPS) can slightly be raised (recalibrate TPS, or use 10k series resistor to decrease this effect). Pressure-sensors (MAP and boost) and MAF are usually conditioned (though we heard that a certain MAF was not)
- 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/Wheel Speed input
- 11: RPM reference (input threshold can be adjusted; leave open)
- 12: 5A Power control
- 13: Power GND connect all GND-s
- 14: Power GND connect all GND-s
- 15: GND (Power or signal) connect all GND-s. If you connect this ground to the EGT- (sensor - white wire) than this can be separate from the pin14 and pin14 (pin12 and pin14 always used for powerGND)
- Also wire supply voltage to WBO2 Heater to sensor pin 3 through 5A fuse (already wired this way in the supplied harness)
