Hello Scott,
Thank you for the details.
The Latency timer and buffer settings are the correct settings to alter in this case.
However as I'm sure you have noticed performance on different machines can vary, this is due to the inherent nature of USB.
USB products can’t reliably be used in real-time applications with time interval resolution guarantees.
Sometimes the behaviour of USB can be a problem and applications cannot be guaranteed throughput.
If there is more USB traffic then the OS and USB have to schedule the communication with each of the USB devices.
It’s highly dependent on the OS and USB Host and is out with our control.
You could take a look at the following App notes:
Data Throughput, Latency & HandshakingOptimising D2XX Data ThroughputThese apply to all of our USB products.
The latency timer can only be set to 1ms minimum for our High Speed USB products and nothing less, and 2ms for our Full Speed USB products (like FT232R inside the USB-RS485-WE cable).
Best Regards.
FTDI Community