Initial Testing and Wiring For Genboard V3.#
You find schematic and layout files on
StepByStepGuide page is very similar with almost the same steps, but with images.
The information from this page is consolidated in the Genboard v3.3 assembly instructions, most of it also applies to to earlier revisions, please take a look at the complete pdf [here]
First of all, please check:
- See how far it was tested and what is in the AVR flash: GenBoard/VerThree/Testing It is recommended that you repeat the last tests - RS232, mdh.., LCD, etc.. without anything special soldered by you (stepper, FETs) - the power (preferrably from a current-limited source of max 500mA) is necessary of course. This way you can find out very fast if any of the things you soldered make any difference in the bad direction (short, or something).
- Components that might come handy: GenBoard/VerThree/RescueKit
- absolutely important before you switch any inductive loads: FlyBack: Low voltage recommended, simplest and coolest: DR with R=0 is recommended (R<=22 in any case, but rather R<=10 for highZ; stick to R=0 for lowZ PWM-ed). The Diode can be any diode with 1A or bigger average, 2A peak; eg. 1n4007 throughole mounted on top SMD style replaces the 0 Ohm too; or S2J: SMB package SMD diode needs 0 Ohm bypass wire)
- if you have FETdrivers you want the power connected to it. Check that there is a short or a diode (with right polarity) in place of D6. (on v3.0 many people used small bypass wires instead of FETdrivers for non-PWM-ing highZ injector setups: these don't need anything at D6; but inverting MC34151D FETdrivers are the upcoming standard, because a box using them can be used for lowZ that way without any HW change; Also, on v3.0 with FETdrivers the SJ1 needs to be configured for 13.8V not 5V)
- GND5 and GND is connected (eg. at D15. This short should be there, since it is used in testing). There are 2 religions. Many people cut this short to keep the voltage spikes in the GND5, and away from GND (and especially AGND). Many people leave this onboard short to avoid voltage between GND and GND5 (that can kill P259 chip in extreme cases with bad installation) In any case connect GND and GND5 in the harness at the battery. In any case, sensors must be grounded at the ECU side (GND signal), not at the battery. The 1-wire narrowband O2 sensor that is grounded via case is usually a problem, but who uses NBO2? Some (NTC) CLT sensors are also grounded to engine via case, but their signal is not very sensitive. (K-thermocouple is sensitive, but grounded at ECU only). See GenBoard/Manual/GroundConnections for a better overview.
- AGND and GND are connected (on v3.1 these are connected with a small short under R30 on the bottom side; some gourmans like other strategy for this connection). Usually left as is.
OLD checklist (v3.0 .. v3.1)
- add some supply caps from the rescue kit on empty supply cap places. Eg. 10uF 1206 10V to near PS2 1x4 header. There are many empty cap-pads for the 12V under the OPAs. You don't need to fill those all, but for any cap you install make sure the cap voltage is sufficient. adding 16V 2.2uF 0805 caps on 12V traces is not recommended, the 1uF 25V is OK. When there are double cap-places parallel to each other, one is usually big, like a 1uF, the other is small like 100..220nF because the small ones are often work better at higher frequencies
If you are doubt which supply caps should be populated, put them all in, as big capacitance values as you have, given the voltage constraints are met. Make sure you put at least 25V caps to the 14V supply (near OPA, stepper and main regulator. The FETdriver already has supply caps on all onboard places).
Check at least C68, C96, C71, C95.
- to check R6 / R13 that is the voltage divider (the lower side resistor was missing on first v3.1 boards which makes no harm but VBatt seems to be maxed out). Set config.batt_cal to match your divider. Don't get scared of the high VBatt reading before you check the voltage divider and set config.batt_cal. It is normal and harmless.
Note: you shouldn't need to soldering extra capacitors to v3.3. See "Recommended checklist" on BuildProcedures/SectionThree
You will probably need these things to start working with your new GenBoard/VerThree
- RS232 Serial Port Wiring: GenBoard/Manual/CommConfiguration. Good idea to get this working first.
- PS/2 Keyboard Wiring: GenBoard/Manual/Keyboard (watch rs232 and issue mcd on PS/2 to test)
- LCD Display Wiring: GenBoard/Manual/LCD
Since the firmware used for GenBoard/VerThree/Testing is not cleared, it is advised that you do not erase your firmware from the AVR until the above test OK (because you add an uncertainty with that). After that you will probably want your own firmware.
- Finishing Assembled GenBoard: BuildProcedures/SectionThree (additional components)
- What do i need for WBO2 wiring: GenBoard/Installation/WBOconnect?
More on GenBoard/VerThree/LowZInjectors and flyback:
The assembled boards since v3.1 are shipped with R154, check yourself. That is pullup to 5V. If you add the SIL5 10k pullup and 2 FETdrivers if you need more than 4 channels (2 are mounted already), the PWM option is there (and even non logic level FETs, though nothing can be as nice as the insulated FQPF FET). The PWM option is not obligatory, of course. If the FlyBack is high voltage, but low dissipation capable, configuring PWM will fry it. It can be prevented by converting high voltage flyback to low voltage Flyback: bypassing the 6.8V or 22V SMB transient protection diode, or the 10..22 Ohm resistor with a short or an SMB diode. See GenBoard/Manual/DDFlyback for information.
Batch firing can be used but is the worst idea
Setting config.alternate=01 and the h table first 2 entries. But why would you load the supply (GND5) and the fuel rail unnecessarily, when you have the option to switch them at different times? To save a few wires?
Use a grounded, electrostatic-free workplace to install the PowerSwitchers?, they are a bit sensitive.
TODO: links about this; describe safe and unsafe soldering iron types