5v ALDL 8192 Baud to esp32

Thread Starter

DBTech7

Joined Apr 21, 2022
30
I've been working on a diagnostics program for my old diesel, I need the TX/RX pins of my esp32 to connect to the 1 wire ALDL port. I believe I've found a suitable way using the following circuit
c20e282968074120e0daf98e2e3b05970a7401cf.png
Im aware this does not include level shifting from 5v to 3v3 which I believe I just need a suitable level shifter ic to accomplish, my question here is how does this circuit allow 1 wire to 2 wire communication? Wouldn't the diode in that orientation not allow the TX pin to send its data?

Here is another interface circuit I found, I'm not sure how both of these circuits could be accomplishing the same thing. Could anyone provide some insight into this and maybe recommend which method is better?
Untitled.png
This is the complete circuit of the one directly above, could someone also explain if the oscillator is needed for the interface or if its simply the clock of the mcu?
Untitled1.png
 
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