Yes logic level between two boards will be 3.3V over 2.5m distance.I assume that the logic at both ends of the link uses 0 to 3.3 volts signals. Is this correct ? Do you want to use a standard signal level for the link between the units such as RS232 or some none standard levels ? What baud rate is the link working at ?
Les.
Thanks for your reply.For 2.5M you may get away with just the port pin, if it is low data rate.
But as mentioned above, more info please.
If you want full duplex, these will work, and for a lot longer distance too.
https://www.ti.com/lit/ds/symlink/sn65hvd30-ep.pdf
Thet are a bit overkill, but why not?
Thanks,
I want to make it very clear that :I am still not clear on the signal levels on the cable between the two units. In post #4 it sounds like you want the signal level on the cable to be 3.3 volts. (The same as the logic levels in the devices at each end) In post #5 you say that you want RS232 levels on the link cable. If you want 3.3 volt levels then The solution suggested by dendad in post #3 is suitable. If you want RS232 then MAX3222
type devices should be suitable.
Les.
Many Thanks !!!From the data sheet in the link I provided in post #7 page 1 shows the pinout and page 8 shows it connected to a UART.
R in is RS232 level
R out is logic level
T in is logic level
T out is RS232 level
Les.