Re: Trying to communicate with 1226865 ECM
Posted: Fri Sep 27, 2019 4:14 am
The purpose of the existing transistor is as a buffer and level converter. The fact that it also inverts is a nuisance in this case.ndndndnd wrote:Do I need another transistor circuit to invert the signal? I thought the 'Q1' transistor (2N3904) in the WinALDL circuit already inverted the signal? I was investigating inverting the signal so I could omit the transistor circuit and reduce the number of variables...
I guess what I'm getting down to is: does anyone know if this circuit should be working, even through the FT232BL chip?
Thanks for your continuing help guys!
ND
The circuit is fine (indeed, looks quite good) if you're driving an FT232RL, because you can enable a further inversion within the chip. But it cannot work with an FT232BL without an extra transistor (and two 10k resistors) to correct the signal polarity.
Joe.