Digital Bus Communication with LabVIEW (SPI, I2C, JTAG)

[SumRunner]

I see more and more applications where SPI and I2C buses are used, and we get questions from our customers about how to access these buses with LabVIEW. I saw today that an engineer at NI developed VI's that you can use to turn any of our hardware-timed digital boards into a serial, SPI or JTAG interface, and any of our tri-state digital boards into an I2C interface.

You may know that we have a $399 device, the USB-8451, which acts as a I2C master interface or SPI:

However, with these new VI's on ni.com, you can use any of our hardware-time digital boards to do serial, SPI, or JTAG communication. A hardware-timed digital board is any board that has the circuitry to internally clock out or in a digital signal. A software-timed digital board is one that sets digital states based on software calls, but a different software call is needed each time you change the states of any of the lines. In general, the low-cost, slow digitial boards are software timed and high-speed digital boards, M-series data acquisition boards, and digital waveform generators are hardware timed.

To interfae to I2C, you need a board that also supports tri-state digital lines. The 655x family of digital products support this communication.