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Pilbox speedup on Mac OS X - Printable Version

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Pilbox speedup on Mac OS X - Håkan Thörngren - 06-07-2013

Just to let you know that it is possible to reduce the latency timer on the Mac OS X side (with VCP driver) to make communications between the Mac and Pilbox faster.

To make it work, edit /System/Library/Extensions/FTDIUSBSerialDriver.kext/Contents/Info.plist and insert latency timer settings.

sudo touch /System/Library/Extensions

then reboot.

I got about 2.5 speedup doing this, much better, though I had hoped for a bit more as the latency timer was reduced by a factor of 8.

Re: Pilbox speedup on Mac OS X - Egan Ford - 06-07-2013

It's been a while (2009), but I had to request a custom FTDI driver for OS/X to even have the LatencyTimer setting exposed. I guess it's standard now?

Anyway, a setting of "2" gave me the same performance as the PILBox on Windows. IIRC, it was the same speed as using real HP-IL gear.