07-29-2015 03:22 AM
I have a NI USB-8452 I2C board which is connect to a device with x24C04 chip fitted. It's address is hard wired to 0xA0.
I have used NI I2C library to attempt to read from the device, but all I get back is an array full of 0xFF.
The LabVIEW is across a couple of VI's but is shown below.
Any ideas what I am doing wrong? I am a bit new to I2C stuff!
07-29-2015 03:38 AM - edited 07-29-2015 03:38 AM
I've not used the NI I2C devices before so I can't really see anything glaringly obvious with the code, but do you have an I2C pullup resistor located somewhere else in your circuit/wiring? As per the I2C standard you need to have pullup resistors located somewhere on SCL and SDA and you have a 'false' wired to use the ones internal on the NI I2C device, so I'm assuming you have them located elsewhere?
07-29-2015 06:21 AM
@Sam_Sharp wrote:
I've not used the NI I2C devices before so I can't really see anything glaringly obvious with the code, but do you have an I2C pullup resistor located somewhere else in your circuit/wiring? As per the I2C standard you need to have pullup resistors located somewhere on SCL and SDA and you have a 'false' wired to use the ones internal on the NI I2C device, so I'm assuming you have them located elsewhere?
Yes. There is a pull up resistor at the device end (where the X24C04 is located). Initially I had the NI board pullup on as well and the I2C VI just error then.