Vehicle Overview:
1989 BMW e30 with a M50b25 NV out of a 91 BMW 525
specs on VEMS:
1 x Assembled v3.6 controller
- 1-wire interface: no
- withSDcard: removable
- PS2 connection: no
- secondary_trigger: HALL Need to convert to VR!
- mounting-style: no-screws
- MAP connection: 400kPa (5/3mm pneumatic)
- LCD connection: no
- EGT input: 1
- Flyback: 30V flyback
- ignition driver: 8
- Knock input channels: 2
- primary_trigger: EC36/27 VR
VEMS was purchased for a later M50 with Hall. This engine has a VR/VR trigger setup. to extend coil life and prevent IGBT's from over heating a cam sync will need to be installed. After following directions on this page: http://www.vems.hu/wiki/index.php?page=GenBoard%2FManual%2FInputTriggerHardWare
this is where the project sits.
removed blob between SOT23 NPN base and collector
_________________________________________________________________
Directions to follow:
while SJ7 is open, with cam-HALL masking signal unconnected you can measure that R48 (2k7 recommended) pulls up D27 cathode to 3.5V or higher. This is a good verification !◦ after SJ7 is shorted, unfortunately this cannot be measured (except with scope with input pulses applied)
• SJ7 solder-blob on the bottom, so LM1815pin12 output is connected to the microcontroller input pin. This blob is on the bottom, under the FETs.
• solder the 2nd LM1815 (same orientation as first: pin1 closest to atmega)
• wire from EC18pin12 to the 2nd LM1815 input pad (that goes through a 18k resistor to pin3 of the second LM1815)◦ 1k pulldown resistor between VR input signal and GND
◦ this is effectively in parallel with the VR sensor. Scratch the green solderprotect a bit at the GND so an SMD resistor can be soldered
• To make it work with the 1k VR-input pulldown resistor, connect LM1815 pin5 to +5V with the SJ4 (3pin jumper): solder the mid-pin to the +5V pin that goes LM1815pin8
• R182=0 resistor (or short) at LM1815pin7. This helps the adaptive hysteresis (quicker charge). Has the same function as R181 >= 100k for the first LM1815 (soldered in factory) but 0 Ohm (short) is more appropriate here.◦ optionally increasing the neighboring 220nF capacitor by adding an additional (solder piggyback) +1uF or +2.2uF might be a good idea
_________________________________________________________________