HI,
There are a lot of differences. (number of channels, differences in data transfer rate...)
In my opinion you should look on their manuals.
NI PXIe 6555
200 MHz, 24-Channel, Onboard PPMU, PXI Digital Waveform Instrument—The PXIe‑6555 is a digital waveform generator and analyzer for interfacing, characterization, and DC parametric testing with 24 single-ended digital pins. The device is capable of sampling digital waveforms at up to 200 MHz and interfacing with user-programmable voltage levels. The PXIe‑6555 also features hardware comparison for bit-error testing, DC voltage and current parametric measurements, and per-pin advanced digital timing features.
NI PXI 6542
100 MHz, 32-Channel, 5 V PXI Digital Waveform Instrument—The PXI‑6542 is a digital waveform generator and analyzer for interfacing with 32 single-ended digital pins. The PXI‑6542 can sample digital waveforms at up to 100 MHz and interface with common transistor‑to‑transistor logic (TTL) voltage levels. The PXI‑6542 also features advanced synchronization capabilities for building integrated mixed-signal test systems.
bhovhann
