Difference between revisions of "FTDI Linux USB latency"
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(Created page with "= FTDI Linux USB latency = 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. Lates...") |
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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. | 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 | + | 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 == | == USB latency setting == | ||
Revision as of 09:52, 25 July 2018
FTDI Linux USB latency
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
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
 | Depending on the system, the USB latency might default back to 16 ms after system startup or device reconnection. |
