ARM based Unidentified Fueling Object - developer info!
The primary application for this board has changed as a result of the ArmEfi growing out of the EC36 connector and the box. The ArmUfo will use the 120X40X2.5mm box and the EC36 connector instead, while the ArmEfi is postponed until we find suitable connector and box.
This board is meant to be the right size for most cars in a standalone application and also scale well when used as a building block in a larger system.
Specification:
Box: Aluminium profile 120X40X2.5mm
Connector: AMP Econoseal III 36 pin.
Internal MAP: Yes, 4bar sensor and 5x3mm pneumatic connector on frontplate. The new small helper board can be used (a sensor with horizontal nipple has better space usage and connection to the frontplate)
CAN: Yes, 1 internal and 1 on EC36 combined with VEMS link.
WBo2: Yes, 1 channel with PNP capability. (although using RCal is really meaningless for an ECM that has 100+ settings anyway and only ment for professional install: RCal just wastes a pin. RCal only makes sense for a standalone meter that can be used by low-qualified servicemen and possibly sensor is swapped a lot when used for testing the sensor itself).
Ignition power stages: Yes, 4. Both can be configured for low voltage flyback (in HW => population time or soldering) if external power stages are used. Current limiting for protection of coils when engine stalls is mostly a software issue 1..3 points on GND5 is measured by ADC so overcurrent or forgotten GND5 is recognized before ECM damage.
Injector outputs: 6, high or low impendance with switched flyback. How do we protect against short circuit?
Trigger: 1VR/Hall channel and 1 Hall only Note, no VR chip. VR analysis made in software after beeing sampled with ADC
Basic sensors: IAT, CLT, TPS.
Pushpull outputs: 4 (using 1 or 2 SN754410 powerdip). The only task these are most useful for is bipolar stepper (usually only found as idle actuator).
Important: flyback-equipped low-side switch is more useful for:
- injector
- fuelpump relay
- boost solenoid
- variable cam timing
- variable intake
- unipolar stepper (the exceptional case where high voltage flyback is better)
- tachometer output (pullup might be needed)
note: we don't want to drive external ignition modules (eg.: 12 push-pull stepper outputs for an 8cyl engine with bipolar stepper would be stupid), except our CDI / ION
VemsLink: Yes (VEMS link is a high speed CAN and two open collector trigger signals that can be configured as input or output.)
Case relevant issues
It is very important to have IO buttons (how many?) on the box, having a keyboard in the car at all times is not practical. This also makes it possible to make a compact hand held tuner that can tune the ArmEfi and other VEMS frontier products. I guess it is the question of a free digital or analog input(s), and the rest is mechanical (case) issue.
MMC slot ?
- I think the MMC can live inside, without the possibility of removing (maybe soldered)
- anyone insisting on removable MMC slot ?
This (armufo??) is a multi application board, it can be used for the following applications:
With (external ?) display and buttons:
- MAF replacement / MAF tuner.
- WBo2 Lambda meter (? why would someone use this instead of a standalone? maybe this is ment logger box with internal WBO2 controller )
- Boost controller.
- Exhaust temp meter.
- Additional fuel controller.
- Handheld tuner for ArmEfi and the other CAN enabled boards. I highly doubt that this would work. A logger and control board can be merged reasonably. A UI (user-interface) board cannot. (well, apexi makes profit from boost controllers made this way, but separated UI and controller is remarkably better).
- Entry level engine management system with integrated display (how?) and user interface.
See also
- VemsFrontier/Boards is the family where this belongs