I2C FTCI2C problem

[bseguin]

This could be due to many factor. Be sure that the address and base address is correct. Be sure that your wire are not too long. One issue I had with some device, is that I needed to add a delay between each read or write that can go up to 25ms. This depend on your wire. You need to be sure that you use the correct mask for the configuration. I do not know your level of expertise in I2C.

[KathrynTheGreat]

Hi SeanJ,

Because this is an older thread, you'll get more visibility if you post a new thread for your issue. On our forums, newer threads appear higher in the list, so you're more likely to get a response that way.

[SeanJ]

Hi bseguin.

Thanks for your reply.

I have a bit of experience with i2c, (SBC and proprietary software) but not through labVIEW.

I am expecting to specify the address, send a command and get a reply using the FTDI cable.  I have 5V pull-ups as the sensor is 5V rated and the cable 3.3V, (I spoke with FTDI and they assured me it should work with the pull-ups).

I'm not sure what you mean by the 'the address and base address'.  What is the difference between them?

Also, what is the correct mask?  By this do you mean what I would call the command?

Thanks,

Seán

[SeanJ]

duplicate... 

[bseguin]

If you look at the manufacturer datasheet, you will see the base address. Then usually you can set 3 other pin for the device address. You might have also a write protect pin in the case of an EEPROM. Can you send details about your setup?

[SeanJ]

Hi bseguin,

There's no setup of any significance.

I have a TE 4525DO-DS5AI015DP pressure sensor.  I supply 5V from a tracopower 5V supply and have two 4.7k pullups resistors connecting SDA --> 5V and SCL --> 5V.  

I try to talk to it using the FTDI 3.3V I2C device which is also connected to the 5V pullups, (this is fine according to FTDI).

Rgds,

Seán

[SeanJ]

I did a quick schematic of the implementation.

[bseguin]

According to the manufacturer datasheet, the base address for your package in I2C interface is I = I2C (Addr.0x28H)

So to access the device, be sure you use the address 28 in hex format.

Benoit

[SeanJ]

Hi Benoit,

I posted my question in a new thread.  It references your code.

http://forums.ni.com/t5/LabVIEW/I2C-communications-using-FTDI-MPSSE-Cable-and-TE-Pressure-Sensor/td-...

I added some traces to show that I transmit 0x28 and 0x51.

[bseguin]

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