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Honored Contributor I

No output from HPS UART during boot

I have a custom board with a Cyclone V SoC. The chip powers up ok and I can see the FPGA and the HPS on the JTAG chain when I use my USB blaster. So far so good! 


I would now like to get the HPS to boot Linux, and then configure the FPGA via Linux. All the information should come from the SD-Card. 

I have an FTDI UART-to-USB chip on the HPS UART 0, so I can see the text output by the Preloader and UBOOT. 


I am using a Samsung 32GB microSDHC card, configured with the relevant partitions, pre-loader, and U-boot, all generated based on my Qsys project and Quartus Prime. 


When the USB cable is plugged in, the PC recognises the FTDI UART chip (as COM4), and I set the baud rate to 115200 baud, 8-bit data, no parrity, 1 stop bit, no flow control. 


The problem is that when I turn on the SoC board, I see nothing coming across the UART to my PC (as viewed using Teraterm) 


I appreciate that there could be all kinds of reasons why this isn't working, but I would welcome suggestions about what to check and I will try as many of those suggestions as I can. 


As an initial sanity-check, can someone please confirm for me what are the correct MSEL, BOOTSEL, and CSEL settings for booting the HPS from a 3.3V SDCARD, then programming the FPGA from Linux. 

Here is what I currently have selected:
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Honored Contributor I


Did you find a solution to this problem? I'm having the same issue...
Honored Contributor I

Hi, in my case, there was a problem with the Altium footprint for the FTDI usb usart chip. The problem was on the solder-mask layer. This was shorting out some pins on that chip during reflow soldering. 



Other things to check is that you have the usart in and out pins the correct way round.