I’m taking a stab at the attached PDF trying to go to arduino.
I’m not planning on using the line labelled L, and I’ve replaced the FT232BM with an arduino.
I’m using SoftwareSerial as it’s a non standard baud rate at 15625 baud, and I’ve added rough timing for that to the library.
I’ve tried connecting but I don’t get any data back - so I’ve taken the circuit connected the K line to a multimeter intending to see the line dip below 1V for 200ms x 7, however during that bit of the code, the line is around 8.35V.
When idle the line sits at 8.95V.
My thought is the RX line is holding it high how I have wired it - so I’ll describe it.
I have replaced SD601 with BC337, I’ve got the K line coming into the circuit and it’s held high with a 1K resistor. On that same line of the breadboard, I’ve got two jumpers one takes the signal to the transistor to be grounded, the other goes to the RX optocoupler.
I believe somewhere amongst this is what is holding it high (I can’t see what I’d call a logic 0 in my testing).
Any thoughts based on the schematic what might be a problem? I assume the schematic to be correct though I did look at the 1k to ground at the base of the transistor as well - changing it to be inline did nothing.
openport.pdf (24.4 KB)