Hello,

The SCK line should normally be a push-pull output on this device (unless your code switches the pin to input mode at any time)

What I/O voltage does your MCU use? Is it a 3v3 I/O

We would recommend to check with a scope or logic analyser with analog capability to see what the waveforms are doing,

Best Regards, FTDI Community

Hello,

That would be the last version of macOS to support .kext drivers, this would be 10.15, but there is an extra notarization step for .kext drivers required by Apple in 10.15, that is not noted in that document. As such it would be safe to assume these instructions work up for drivers up till macOS 10.14.

Best Regards,
FTDI Community

Hi,

The FT2232H defaults to 2 x UART ports. Using the MPSSE for SPI requires additional commands from the application itself,

The FTDI chipsets are vendor class devices and so require a driver on the host, if you run Linux on the host computer/MCU please ensure the Linux build includes the FTDI driver.

The Linux build may include an sio driver which is part of many distributions. However, MPSSE (for SPI) will require you to load our D2xx drivers which can be obtained from our D2xx drivers page. We have these for various Linux platforms but it will also depend if the Kinetis uses one of our supported processor types,

Best Regards, FTDI Community

Hi


Power Sequence

It is recommended that VCC, VCCIO and RESET# are set at the same time, I would suggest connecting RESET# and VCCIO to 3V3OUT as this will ensure these are set when VCC is powered.
 
Mixing a bus and self-powered design is not recommended.  VCCIO should be connected to either 5V or 3.3V in one of the following configurations:
 
•   Entirely bus powered, that is from the USB port (VCC and VCCIO pins).  In the case where 3.3V IO's are required a local 3.3V regulator is needed which can be supplied from the USB bus.  Alternatively, in some cases, where only a small amount of current is required (< 5mA), it may be possible to use the in-built regulator of the FTDI device (where available) to supply the 3.3V to VCCIO without any other components being required.  In this case, connect VCCIO to the 3V3OUT pin of the FTDI device.
•   Entirely self-powered, that is from the local supply on your board.  In the case where 3.3V IO's are required, you will need 5V and 3.3V to be available on your board.


Crystal Frequency

Section 6.3 of the FT2232H Datasheet gives an example of a 12MHz crystal being connected in the oscillator configuration.


Suspend State
 
You can read about USB Selective Suspend in AN_107 Advanced Driver Options.

We tell the system we're idle and the system puts us in a low power state.

If it is in selective suspend, the next request through the driver will bring it out of suspend.

For example, in a terminal emulator open port, no data for say 5 seconds will put the device into suspend. The next keystroke will generate a write request. When the driver receives that request, it will come out of suspend and send the data.

There is also an additional feature called remote wake-up which can be used to bring the device out of suspend mode:

RI# pin: Ring Indicator Control Input. When remote wake up is enabled in the internal EEPROM taking RI# low (20ms active low pulse) can be used to resume the PC USB host controller from suspend.

Suspend mode can be monitored via the SLEEP# pin.

please let us know f you have any other questions.

Best Regards

FTDI community

Hi,
As per the installation guide, the VCP driver is part of the kernel in versions 10.9 and later so it is there by default   

Best Regards
FTDI Community

Hello,

You should try uninstalling the drivers using our CDM uninstaller utility. Then install our windows driver:

https://ftdichip.com/drivers/vcp-drivers/

However Device Descriptor Request Failed usually points to a hardware issue. Please contact your local support team and include your schematics:

https://ftdichip.com/technical-support/

Section 3.2.2 of the device datasheet describes the pin configuration to use the device asynchronous mode.

Best Regards,
FTDI Community

Hello Scott,

Thank you for your question.

I would like to apologise that you haven't be able to contact any via phone in the UK office, unfortunately we are still working form home currently.

We are currently investigating how to generate a codeless .dext wrapper for any Info.plist modifications which might be required by an end user.
Is this what you are trying to achieve?

Could you describe the latency issues you are seeing?

Hello.  My name is Scott Miller and I am a BCI researcher.  I too am experiencing severe latency issues with the VCP driver on macOS 11.  I am using a MacBook Pro M1 running the latest version of Big Sur.

I read this entire thread and several others blog threads across the internet.  I emailed and spoke with Cameron from FTDI tech support in Oregon.  Cameron was very helpful.  He let me know that the latest 1.4.7 driver runs on both x86_64 and arm64.  I tried modding the 1.4.7 driver on my M1 but ran into the same code signing issues described by others in this thread.

Cameron also reached out to the FTDI team in the UK on my behalf.  That team replied with some links which talk about how to build my own driver, but that's not very useful to me at this point in time.

I also tried calling tech support in Glasgow, during normal working hours in GMT, but was unable to reach anyone at all.  The voice mailboxes are all full, and not even an operator answered my calls.  I tried repeatedly.

I suspect that FTDI is for some reason unable to obtain a DriverKit entitlement from Apple.  Is that the case?  Has FTDI made any progress on this issue?

Best Regards,
FTDI Community.

Hi,

Glad it helped,

Yes, the FT4222H offers one SPI Master (SCK/MOSI/MISO) with up to four chip selects,  or one Quad SPI (this uses four bi-directional data lines and is used by some devices such as flash chips or Bridgetek EVE chips) or one I2C Master or one SPI slave (MOSI/MISO/SCK).

It uses hi-speed USB and bulk transfers and so offers quite a lot more throughput,

Best Regards, FTDI Community