Hi Tony,

Your only option would be to add some external pulldown on the GPIOH pins. Even if they have been set as low and input, if there is no connection they will be pulled high by the internal pullups.

Best Regards
FTDI Community

Hi,
  I do connect the GPIOH with the slave device, I use GPIO to listen pull-high signal from the slave when the slave have data to send to the master via SPI.
 
  It works on our windows application used 232H and slave device when they are both power on. but it is a little bit bothered that I need to add time stamp in the test log and find out the first successful transfered message.
 
  I expect that I run my windows application first, and power on the slave device in second action, then the first log message on the application is what I need. so far, I will get the redundant message because of the default state "TriSt-PU" when starting to run the application. On my current test SOP, the default state is the fake signal for my application. How do I bypass this default state?

8. TriSt-PU – Input pulled up, not used

  Is the definition of TriSt-PU as defined above? What is the definition of "used"? I use FT_writeGPIO() to initialize to zero, is it not defined as "used"?

Best Regards
Tony

Hi Tony,

The default for these GPIO pins is TriSt-PU. See table 5.1 in FTDI Device Input Output pin States.

what are you planning on connecting the GPIOH pins to? have you tried connecting the pins to a slave device and performing a GPIO read?

Best Regards
FTDI Community

Hello,

When using LibMPSSE, GPIOL[0:3] can only be used as SPI chip selects.
 
When using LibMPSSE, there is no way to control GPIOL[0:3] as GPIO.
 
LibMPSSE demonstrates controlling the higher line bytes (GPIOH) while using SPI on the lower line bytes using the following functions:
 
FT_WriteGPIO
FT_ReadGPIO
 
If you want to control some of the unused lower line bytes on the same ADBUS as SPI then see AN_411 FTx232H MPSSE I2C Master Example in C which demonstrates GPIO usage with MPSSE using D2xx direct (not using LibMPSSE).
This could be used as a base to understand using both SPI/GPIO in the same code.
OK this example is for I2C but the same principles apply to SPI.

Best Regards
FTDI Community

Hi everybody

I'm trying to read an external I2C 24LC256 eeprom content using a FT2232D connected to the computer with USB
I have a very old (2007) c++ application that works and I can see the signals with a logic analyser (az delivery + saelae)

But when I try to do it with a new c# code, it fails. Here is my code to read 32 bytes

using Iot.Device.Ft232H;
using Iot.Device.FtCommon;
using System.Device.I2c;
....
Ft232HDevice ft232h = new Ft232HDevice(FtCommon.GetDevices()[0]);
I2cConnectionSettings i2cSettings = new I2cConnectionSettings(0, 0xA0);
I2cDevice i2cDevice = ft232h.CreateI2cDevice(i2cSettings);
byte[] b = new byte[32];
i2cDevice.WriteByte(0);
i2cDevice.WriteByte(0);
i2cDevice.Read(b);
Console.WriteLine(BitConverter.ToString(b));

When I look the logic analyser, there is no signal between the FT2232D and the EEPROM
It would be great if someone could give me any idea to fix this...
Thanks

Hi,
  I got the issue that the FT_ReadGPIO read all bit values as high(255) after setting up the initial value as low(0) for all bits.
 
  first, I set up the GPIO initial value as low and direction as input by FT_WriteGPIO(handle, 0, 0);
  then, I use the FT_ReadGPIO(&read_value), I always get 255 when the GPIOH has no connection.
  If I connect one of the GPIOH to the GND pin, the reading will change to low, it comes back high when removing the connection.

  Is it the expected behavior of the GPIO within LibMPSSE?

  My environment:
  LibMPSSE version: 1.0.5
  Device:232H
  OS: Windows
  Pin usage: SPI for GPIOL[0:3], GPIO for GPIOH[4]

Best Regards,
Tony

Hello,

Please confirm which version of the D2xx driver and LibFT4222 that you are using?

Are you using custom FT4222H hardware? Do you see the same issue with our UMFT4222EV-D?

Could the I2C slave be at fault rather than the FT4222H I2C master?

When this happens maybe you can perform a software reset rather than having to force quit or restart?
See FT4222_ChipReset API. You can also try these D2xx based APIs:

FT_Purge
FT_ResetDevice
FT_ResetPort
FT_Rescan
FT_Reload
FT_CyclePort

Best Regards,
FTDI Community

We have systems communication over I2C with a Windows machine acting as master. The system will chug along doing millions of messages over weeks or months just fine, or it may run for a few hours then get an FTDI error. When this happens, the program is usually locked up (spinny blue donut) and we have to force quit or restart Windows.

When that happens, I do not expect there is anything we can do about it.

But other times, we'll sometimes get back the error 1011 (failed to read device) error and not lock up, but all further I2C writes will be failing with errors.

Do we have any hope of finding a way to prevent this from happening?

Hello,

Unfortunately the LibFT4222 source code can't be shared as it's exposes secrets of our vendor class devices.

Please contact us via email on support1@ftdichip.com and we'll contact our R&D team to see if we can provide a 64 Bit (aarch64) build.

Best Regards,
FTDI Community

It is becoming more and more common to install a 64 Bit OS on a Raspberry. Libft4222 is available for ARMv8 32 Bit architecture, but not for 64 Bit (aarch64). When will you publish it or when will you publish the source code of LibFT4222 so that we can compile it on any architecture?

Thanks.