FTDI's R, C and BM series chips allow the latency timer to be changed from 16 milliseconds to any value from 1 to 255 milliseconds, in 1 millisecond increments. When using the FTDI Virtual COM Port driver the latency timer can be set in the port properties page. In Windows, the port properties page is accessed via the Control Panel > System > Device Manager. For Windows 2000 and XP, the initial value of the latency timer can also be pre-configured in ftdiport.inf by changing the value of the last number in the following line:
where again, 16 milliseconds is the default value.
When using FTDI's D2XX direct driver the function FT_SetLatencyTimer can be used to adjust the value of the latency timer.