GenBoard/Manual/KnockInput (2015-01-01 07:00:00)

Normally order VEMS ECU with the correct number of knock inputs and see GenBoard/Manual/KnockSensor and [VT help knock configuration]

If missed to order VEMS ECU with the correct number of knock input - or need some deeper diagnostics, you're on your own, but these can be useful (and the HW is not very complex at all):

How to install if home-modding ?. Take ESD precautions !

AFAIK that is all, but we test it (and enabling: configuring it is needed).


The knock schematic and layout is exactly same on AAN as on

v3.6 or other v3.x, see GenBoard/VerThree/Schematic

The signal path is only a few resistor and capacitor, if the TPIC8101 is there with the 4MHz quartz, not much else to it. See below while following schematic if need more.


Old, but hasn't changed AFAIK

There is also an analog signal output from [TPIC8101] => AVR ADC

GenBoard/VerThree knockdetection HW

Needed for Knock Sensor input:

R1, R2 Knock Channel 1 (10..22k) (analog signal amplitude gain can be adjusted with these; but also in the digital domain - in config)
R3, R4 Knock Channel 2 (same as R1,R2)
R17 1M
C1 Knock Channel 1 (100nF)
C2 Knock Channel 2 (same as C1)
C14 0.22uF
C16 100nF
C18, C19 22pF
Y2 4MHz XTAL (16MHz might work with matching config)
U5 TPIC8101DW (not in rescue kit! Optional, see WebShop)

C17 is no longer used. (was: 2.2nF, can now be left off)

V3.2: if you ordered knock-kit (in same order as genboard) than U5=TPIC8101DW and Y2=crystal already soldered onboard (crystal missing on a few boards sent out before 20041030.)


Here you find the top-side components, the second channel uses components on the bottom side too. (thanks to Mr Grogan for pic)

v3.3_vems_knock_components.jpg

The knock sensor chip installation:

Pin 1 points to the connectors-side. (so pin 1 points to the short side of the board)

KnockChipPads.jpg

KnockChipInPlace.JPG

The crystal goes next to the chip.

KnockChipCrystal.jpg

For the 2nd channel, the following components are also needed:


v3.3

The knockchip and 4MHz crystal is installed (if ordered v3.3 with knock-kit), the only thing needed is to connect the sensor input through the 3 pin header (pads) at the northwest corner (looking at the "top") :

TODO: take pictures of board region around knock chip

If the knock signal is not routed via EC18, it can be routed through a connector or flying loom cable mounted through frontplate or endplate.