MembersPage/KarlBuchka/Trigger (2008-07-11 21:59:49)

Inline 5-cylinder, sequential ignition with camsync

Primary trigger: 60-2 w/ VR sensor.

Secondary trigger: Single tooth w/ Hall sensor.

Firing order is 1-2-4-5-3.


MembersPage/RonnieH has set up VEMS on a very similar motor also with seq. COP. After some additional reading, his settings seem obsolete due to code changes.

Primary trigger settings

Field name Variable name Value [decimal] (Value [hex])Comment
Primary Trigger primary_trigger 1 (0x01) For multi-tooth trigger without filtering (I think). 0x09 is with filtering? Which should I use?
Edge   Rising
Type   Multitooth
Filtering...Bit7   Disable
TDC after the trigger ign_tdcdelay 120 (0x78) Number of degrees BTDC that trigger_tooth is located at, in units of 0.5 degrees. Ex: If trigger tooth is located 60 degrees BTDC, then ign_tdcdelay is 60 * 2 = 120 decimal = 78 hex. Thanks to MembersPage/BorisRieken/PrimairyTrigger for actually taking time to write this shit out.
Number of teeth on wheel tooth_wheel 58 (0x3A) 
Trigger tooth trigger_tooth 6 (0x06) (from memory, need to confirm on engine itself) Look at the tooth under the sensor at TDC of cylinder 1, count backwards the number of teeth required to be ~60 degrees BTDC, the tooth now under the sensor is trigger_tooth
Next trigger tooth another_trigger_tooth 24 (0x18) (from GenBoard/UnderDevelopment/FirmWare/TriggerRelated, 60 (teeth on the wheel) * 2 (wheel revolutions per cycle) / 5 (ignition events) = 24 teeth between events
Crank min. period crank_minper 188 (0xBC) 60 (seconds) / 8000 (max rpm) / 5 (number of engine events) * 2 = 0.003 (seconds) = 3000 (microseconds). In units of 16usec, so 3000usec / 16 = 188 [decimal] = BC [hex]. Can someone confirm this is the correct formula? Or even what this value means?

Secondary trigger settings

Field name Variable name Value [decimal] (Value [hex])Comment
 secondary_trigger (0xFE) For rising edge trigger
 tooth_wheel_twidth1 24 (0x18) Width of a single tooth on wheel, in quarter degrees (360/60 = 6 degrees per tooth, 6*4 = 24 quarter degrees per tooth, 24dec = 18hex)
 tooth_wheel_twidth2 0 (0x00) Not sure on this one either, changelog says set this to 0, but why?
Rising Edge cam_sync_r_edge_phase  
Falling Edge cam_sync_f_edge_phase  
Engine phase, when to reset reset_engphase_after  

Ign. outputs will connect as follows (for 2+6 configuration, according to PhatBob's User Guide):

Cylinder Ign. channel ECU Pin h[2] value* h[1] value**
1 0 EC36/35 00  
2 1 EC36/33 10  
3 4 EC36/11 40  
4 5 EC36/12 50  
5 6 EC36/24 60  

*h[2] is ignchannel array, h[2] = 60 50 40 10 00 00 00 00

**According to the changelog for 1.1.x: h[1] is the reference tooth array (trigger_tooth and ign_tdcdelay is added to this to get TDC), for each output specified in respective h[2] entry.

Confirmation on the above values would be greatly appreciated.