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John Firestone · 08-31-2015, 01:03 PM

You are quite welcome. I am glad you got things straightened out.

I am pretty sure both signals use 12V open collector logic – at least that's how I have been treating them for the last 15 years

– with a resistor in the receiving module pulling a line up to 12V, and an open collector transistor at the driving module pulling it down to ground.

I am have been using a VNS14NV04 as the open collector driver. I have a receiving microcontroller present a ca. 20K input impedance with a 22K pullup resistor to 12V, with an on/off threshold at 5V. I RC-filter the ABS speed signal with a time-constant of ca. 8 µs. I sample with no electrical filtering, the vehicle speed signal from the cluster at 10 khz, but require it to be four times on more than off, or four times off more than on, to change the filtered input state.

08-31-2015, 01:03 PM	#14
John Firestone Senior Member Join Date: Nov 2004 Location: Bremerhaven, Germany Posts: 977 iTrader: (0) Photo Gallery	You are quite welcome. I am glad you got things straightened out. I am pretty sure both signals use 12V open collector logic – at least that's how I have been treating them for the last 15 years – with a resistor in the receiving module pulling a line up to 12V, and an open collector transistor at the driving module pulling it down to ground. I am have been using a VNS14NV04 as the open collector driver. I have a receiving microcontroller present a ca. 20K input impedance with a 22K pullup resistor to 12V, with an on/off threshold at 5V. I RC-filter the ABS speed signal with a time-constant of ca. 8 µs. I sample with no electrical filtering, the vehicle speed signal from the cluster at 10 khz, but require it to be four times on more than off, or four times off more than on, to change the filtered input state. Last edited by John Firestone; 08-31-2015 at 01:10 PM.