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.

Hello,

The extra bytes may be due to lack of biasing on the RS485 transceiver. If you could email into support1@ftdichip.com we can share the RS485 biasing schematic that will be able to help you.

Best Regards
FTDI Community 

Hi everyone,

I have a problem like I mention in title shortly. I designed a board to communicate between pc and a device which use RS485. I can communicate but every time receive a data it comes with a FE or FF byte as prefix. I'm using FT2232HQ with ADM3485EARZ-REEL7 on my board. Then I used USB-COM485-PLUS2 and I compared the waveform of the two converters. Even though the waveforms are same, I did not receive any extra byte while using USB-COM485-PLUS2. I wonder if I get schematic of COM485-PLUS2? Or does anyone have an idea about that situation?

Thank you.

Cristian