problems receiving fast uart data

[uglyoldbob]

I am having difficulty receiving uart data with this code (I am running an atmega16u2 on 8mhz). Data is inconsistently received (115200 8n1 data). The issue seems to be related to the time between bytes received (it is practically 0)

[tewarid]

I wonder if the host is sending baud rate using SetLineCoding. What host is the atmega16u2 board talking to?

[uglyoldbob]

Ive measured the baud rate of transmissions (with an oscilloscope) and they appear to be spot on. In fact if i run a loopback cable, transmissions are received fine. It's when the received bytes are packed super densely that problems occur. (The external device is an embedded platform running u-boot).

[tewarid]

If I understand you correctly, at lower baud rates, let's say 9600, you don't see any issues. Correct?

[tewarid]

Try setting F_CPU and F_USB compiler flags to 8000000UL.

[uglyoldbob]

Ive set both flags as such. I thought the issue was related to the length of idle time between bytes, but after comparing a working stream against a non working stream (both at 115200 baud) i didnt see a difference. Both had zero idle time between bytes.