You can't change SPIM DATA WITH in time to time.
That is a especial requirement, but doable, I think.
Use 2 SPIM (7bit, 8bit) in parallely
Or switching time to time, by control signal.
Reading the data sheet, I don't see the need for 7 bit transfer. The TLC5922 wants to get either 16 bits (2 bytes) or 112 bits (14 bytes). The first amounts to 1 bit per LED, the second one to 7 bit per LED. But for both you can use a SPI master configured to 8-bit-words.
Several possibilities -
1) Create your own SPI out of existing module or a LUT + Logic.
Componet author guide will help. There are also videos on component
2) I looked for a register in TRM, I could not find, but look at where
SPI_DATA_WIDTH is used in project, maybe that will point to register
that controls width. Then look in Reg TRM for its usage.
3) Using just SPI, control its output with a LUT to alter ?
@dana see above - there is not even the need for 7bit transfer, since the TLC5922 expects a whole set of values, so one can use 8bit mode always...
One thing to note here: since you need to send more than 4 bytes (the length of the hardware FIFO), you propably will increase the buffer size of the SPI component. This will then change the implementation to use an internal ISR to fill the hardware buffer.
If you then use SPIM component to control the slave select signal, this signal might go high even when the buffer is not empty. This is because if the SPI is too fast, the hardware buffer runbs empty before the ISR was able to re-fill it. Either you reduce the SPI clock frequency, or you control the slave select line manually via a control register.
Thank you all for your help. but I have 10 TLC5922s to control in a single SPI chain. So I do fill the FIFO in a ISR. but now, it seems doesn't work. I'm trying to find out the preblom.
Are you able to control at least one TLC5922 properly? What is the SPI clock frequency? How is your SPI master set up?
Just stating 'it doesn't work' is not helpful, since my crystal ball is still in repair :(
Maybe you upload your project for us to look?