FTDI Linux USB latency

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FTDI Linux USB latency[edit | edit source]

By default, FTDI chip introduces 16 ms delay to reading from a USB port. In practice this means, that SimpleMotion update rate stays too low.

Latest version of the SimpleMotion library tries to change this automatically. However, due to permissions etc. it might be required to do this manually.

USB latency setting[edit | edit source]

Check "/sys/bus/usb-serial/devices/ttyUSB0/latency_timer" and change the value to 1.

This can be done with e.g. the following terminal command with administrator permissions:

echo 1 > /sys/bus/usb-serial/devices/ttyUSB0/latency_timer

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