Are SPI register write commands ever ignored on-chip?

I’m working with the DWM1000, just getting my feet wet interacting with the registers. I tried writing five bytes to register 8 and then reading them back and I get sporadic behavior. Sometimes the write doesn’t seem to take at all in that the subsequent read doesn’t return my bytes. Sometimes it seems to write the first two or three of the five bytes, but not all five. Sometimes two bytes go in, sometimes three, but never the last two bytes for some reason, and of concern it appears to be rather random how many bytes are successfully written.

Are these registered “protected” somehow? I admit I’m not trying to write meaningful data yet, but sequences, like [1, 2, 3, 4, 5]. Is the chip protecting the registers against potentially meaningless values?

You should look at the UM about register bit field descriptions and if any bits are reserved etc.

Register 0x8 is used for TX frame control. If you are just testing your SPI read and write functions, I would recommend using register 0x21.

I was using register 8 on purpose, as I am working toward data transmission experiments. I just thought I might write all over those 5 bytes while I first got going on it, even though I would have to put meaningful data in before I could actually transmit any data.