SPI transaction, setBitOrder setDatamode setClockDivider

Projects Programming
1

Hello,
I dont understand well the transaction concept and have few questions about it.

In the SPISettings there no place for setBitOrder, setDatamode, setClockDivider ?

So if I have many SPI device, and for exemple bitOrder is not the same for all device, I have to tell at every transaction the bit order ?

What is the right place to put thes parameters ? Is that possible to put it before the SPI.begin ?
Must I put these code after the beginTransaction or before ?

Many thanks for your help and information.

Best regards

Thierry Vorms

2

edit: deleted my somewhat speculative and incorrect post.

3

I documented some of the newer ways of doing things here.

This is part of my page Gammon Forum : Electronics : Microprocessors : SPI - Serial Peripheral Interface - for Arduino

4

Hello,
Many thanks this is more clear.

I have an old library and I have to convert it to transaction model.
The old library use SPI_CLOCK_DIV4.

What must I put to the first param of SPI_Settings ?

Many thanks for your help.

Best regards

Thierry

5

The new library uses the clock rate (it does the division for you). So for a 16 MHz clock, which you want to divide by 4 it would be:

16000000 / 4 = 4000000