Quote: Originally Posted by Vicne
- the fact that CristianC could connect the pin directly to a PC. Indeed, at 1V/12V, the use of the MAX 232 is questionable for most recent PCs that have their threshold above 1V. I would like to hear the opinion of people used to serial communications (Ale again ?) about the removal of the MAX3232 altogether... Only for data coming from the PC probably would it be wiser to change levels I think (at least to avoid sending negative voltage to the CDC)
(*) in fact, the divider could probably be removed too.
I think that if the max3232 without the divider, receive data correctly, you can connect the HU to pc rs232 directly, becouse PC receiver probably is max232 or similar (I have found another EIA-232-D/V.28 driver/receiver
MC145406 that has the same threshold: "The actual turn-on input switchpoint is typically biased at 1.8V above ground, and includes 800mV of hysteresis
for noise rejection. The nominal input impedance is 5k").
for the connection of Txd PC-HU i'll think for a simple schematic with a transistor or a cmos buffer...
good night!!
