Category: DSP

Phasor clock

A sample accurate version of the Max metro object.

Screen Shot 2015-03-09 at 10.34.27 PM

Detects state change when a phasor goes from one to zero. I first saw this in a patch by jhno. Here is a tutorial by Cycling 74:

This patch is used as a clock in an RTTY (frequency shift keying) project. It uses the count~ object instead of phasor~ because its easier to restart the clock at zero phase.


folder: phasor-clock


  • phasor-clock.maxpat

Mac OS frequency control for Softrock SDR devices


By VK6JBL (Andrew Nilsson)

Available for download at

Note: You need to join the Yahoo softrock40 group to access the link

More information about Softrock using Mac OS here:

By Peter B Marks

Note: On Mavericks you may need to unload the kext for the USB device before plugging in the Softrock:

sudo kextunload -bundle

Screen Shot 2015-02-01 at 1.56.18 AM

 update 3-2016

Using the method above gives error messages, similar to:

(kernel) Kext /System/Library/Extensions/AppleUSBFTDI.kext/Contents/MacOS/AppleUSBFTDI not found for unload request.
Failed to unload /System/Library/Extensions/AppleUSBFTDI.kext/Contents/MacOS/AppleUSBFTDI – (libkern/kext) not found.

Various suggestions:

Reboot the computer. Run the command again. Ignore the error message. And then try plugging in the softrock again.

Tried some variations of the command…

sudo kextunload -b /System/Library/Extensions/AppleUSBFTDI.kext/Contents/MacOS/AppleUSBFTDI

But the following one seemed to do the trick (at least for now) even though it still gives an error:

sudo kextunload -bundle-id com.FTDI.driver.FTDIUSBSerialDriver

For a more practical solution, check the FTDI manual, if it makes any sense to you.



A linux command line utility to control softrock, also  by Andrew Nilsson

Local source is in tkzic/softrock/usbsoftrock

Online repo: (last updated 2/2011)

It appears that this may have the code needed to build a Max external.

Soft66lc FTDI driver issues in Mac Os

Notes: Since Mavericks, the Soft66lc SDR external has not been working in Max. Although I was not able to update the external, there is a temporary workaround.

Mac OS is hijacking the FTDI USB device with its own driver. You can unload the driver from terminal:

sudo kextunload -bundle

To reload the driver use “kextload”.

Here is  article from Sparkfun with details about this workaround:

And a more elaborate workaround that removes the Apple driver:

Notes about latency and FTDI

The real solution involves using the new Apple driver to communicate with the device:

Or spoofing the driver with a codeless kext: