I am trying to use the MAX13487E RS485 transreceiver with a Raspberry Pi 3 B+. I chose this chip specifically because it does not require a RTS signal, which is complicated to setup on the PI. My schematic is the following:
The MAX13487E is a 5V chip so I stepped down the RX signal to 3.3V, but I directly connected the TX line to DI, which I think should be fine because the datasheet states that the input high voltage of DI is 2V.
I am receiving data correctly on the PI, but I can't send anything without the other device rejecting frames because of a noisy signal. Here is a scope capture of the TX line in yellow and the RS485 B line in green. This capture was done without connecting the device to the bus.
And here is a capture of the differential signal (pink curve is A - B):
Should I be feeding a 5V signal to DI or is something else wrong with my circuit?