nRF52849 - SPIM: problem using 3 instances

[Kostic]

Good day, dear developers,

I am using nRF52840 with SDK15, no OS. System has 4 SPI devices (2xSPI, 1xQSPI, 1xLCD controller SPI) and 1 - I2C, all having dedicated bus (no sharing).
Configuring 2 SPI devices + 1 I2C works just perfect.
However, 3 SPI dev configuration is causing issues: no transaction occurs on 3rd device; though, neither initialization nor xfr - does not return any error; just nothing happens on the bus.
Questions:
1. Are there any HW/driver limitations to use 3 SPIM instances and 1 TWI? Any known problems with QSPI if added as 4th dev?
2. What about easy DMA config? Can it be enabled for all 3(4) channels?
3. If (1/2) has issues with driver - was it fixed in later SDKs (17) ?

I wish everyone success in development and beyond! Thanks.

[ovrebekk]

Hi

Can you let me know which peripheral instances you are using, and what the instance is for the '3rd device'?

Are you able to use the 3rd device if you disable one of the other peripherals?

1. No, this should be possible, as long as you use TWIM0 with SPIM1, 2 and 3, or TWIM1 with SPIM0, 2, and 3. 

2. Yes, all the EasyDMA channels are dedicated to their own peripheral. There is no sharing of EasyDMA channels between multiple peripherals. 

3. This is not a known issue with SDK v15. 

Best regards
Torbjørn

[Kostic]

Thanks for the reply!
1. We are using SPI0 + SPI2 + SPI3 + TWI1. So, based on your comment this config should work.
2. Device #3 is on SPI2 instance. In other words, SPI0 + SPI3 + TWI1 works fine. But when we add SPI2 - nothing happens on SPI2 bus (no issues with other instances, and no driver errors).
3. I tried to hook up device 3 to instance SPI3 (and disable SPI2) - it works ok then. But I haven't tried just to disable SPI0 or SPI3 to see if SPI2 then works. Will try!

[ovrebekk]

Hi

Just let me know how the test turns out. 

Are you able to share your sdk_config.h file with me?

Best regards
Torbjørn

[Kostic]

Thanks for your support! The problem was related to configuration of SPIM0..3 instances (conflict between SDK code and certain things that we overrode).
So, nRF / SDK works fine!

[ovrebekk]

Hi 

Great to hear you figured it out. I will consider the case resolved then

Best regards
Torbjørn