Is it possible to slow down the I2C rate from 100kHz to 20kHz or lower using MyRIO-1900?

[Timri85]

Hi! 

I couldn't find any thread which addresses my problem via search.

So here is my problem: I need to slow down the I2C speed from 100kHz to around 20kHz. Is that possible using the express VIs? I don't want to use bit-banging. I want to use an 8051 as I2C slave, but it is too slow for 100kHz I2C bus to read the address byte.

Another option will be to clock my 8051 with a much higher rate, but my favorite solution would be a slower I2C frequency coming from myRIO. Thanks in advance!

[FlorianF · Accepted solution]

Hi Timri85,

thank you for your question.

Unfortunatly you can use the low and high level VIs for I2C communication only with the standard transfer modes (100kbps and 400kbps).

Own transfer speeds are only possible when you implement your own I2C Master on the FPGA. Therefore please see the following link

https://www.ni.com/en/support/downloads/tools-network/download.spi-and-i2c-driver-api.html

Best regards