High frequency input on 3.57 main board

[shaodome]

I'm in the process of setting up traction control on a supra using the front and rear ABS sensors. Both of these have a high number of teeth (42) and the flex input on the 3x board is being used by the flex sensor. The only other high frequency input I know of on the 3x card is PT4, so that is what I'm going to use for one of the wheels.

I'm using Jean's VR 2.1 board, which outputs a nice 5v pulse.

Can I just take that output for VR2 with a 1k resistor inline and bring it right to JS4? I don't know if that input can handle the frequency? I know the other inputs on the 3x board drop out right at 49mph, so they can't handle the frequency.

[grom_e30]

Pin 'JS10 PT5' is also available but requires hardware modifications inside the Megasquirt case.
Sources state that sensor wiring is:
+ = 12V ignition live (hot in start and run)
F = frequency output
- = ground

Note that PT4 and PT5 are the most suitable input due to their high frequency capability

that was lifted to do with the frequency maf's from the manual 'js10 pt5' may be good if you can use that, im using pt4 for my front abs sensor 48 tooth works good as far as iv tested.

[racingmini_mtl]

If your dual VR board is installed inside the MS case then you can connect the output directly to either JS10, JS4 or JS5 (ignore what I said on my forum about having to build a circuit).

Jean

[shaodome]

If your dual VR board is installed inside the MS case then you can connect the output directly to either JS10, JS4 or JS5 (ignore what I said on my forum about having to build a circuit).

Jean

Its not in the case, but I can bring it to the pad on the 3.57 board easy enough. Would you suggest at least throwing something like a 1k inline between the output of your board and the JS10 input on the 3.57?

[racingmini_mtl]

Would you suggest at least throwing something like a 1k inline between the output of your board and the JS10 input on the 3.57?

Yes. And you want that resistor inside the MS case to really offer its minimal protection.

Jean

[matthunter1448]

was wondering about this as well i have the external board and am bringing the output in through spark a wire on ms3v3.0 plug do i need to make a circuit or am i also good just using the 1k resistor then to js10,js4?

[matthunter1448]

any body?