Problem with multiple SPI connections

WisBlock
1

Hello,

Im using rak4630 in baseboard rak19001 with two ultrawide band modules in IOs, i have been working with the selection resistors for spi in order to have different CS, RST and IRQ and from that point i have not got any problem for weeks. But recently i wanted to add an external SD card reader like the typical from arduino. I connected all miso, mosi and clk throough the pin headers J15, and im using pin WBIO7 as chip select. This connection only with mcu and sd works well. But when i connect everything (2 UWBs and SD card reader), the uwb stop working, im looking if any pin has conflict but i couldn’t see any problem. Im using libraries DS3231-RTC and UWB from rak4630. I also have seen that when i use sd card begin function the rest crashes…
Any idea? thanks in advance

2

Can you share more details from the external SD card reader?
You say UWB modules stop working, but is the RAK4631 working? Does it startup?

3

Screenshot_20240212-003526
Screenshot_20240212-003526979×473 300 KB

Yes im using one of these sd cards. The rak cpu continues working because i can read and write on the sd card. But is like the uwb lines are not available or not responding. Ill try to bring more details

4

Looks like this is a 5V module, I see voltage regulator on the VCC input. I saw such boards that work with both 3.3V and 5V. Not sure about this one.
Did you measure the voltage levels of MISO/MOSI/SCK on the module?