Cyclone V DevKit with HPS disabled, GPIO does not work

Hi,

I am testing a custom cpu on SoC Devkit, since I don't need the presence of ARM HPS, I just

program directly the .sof file into the FPGA, and running in with the sdcard removed (I have another

project inside sdcard which is running GSRD on that sdcard).

Currently, I am testing a custom uart module and trying to print some letters from cpu through uart.

The tx pin is assigned to one of HSMC pinout (PIN G13), I use GPIO breakout board provided in the box,

In my other project, the gpio can output signal without problem, however, although I can see the signal

is outputting from tx on SignalTap, I can't observe any change on GPIO pin on my oscilloscope..

Is there any special configuration needed to run the Cyclone V FPGA without the HPS??

Thanks.