I have developed a custom carrierboard following NVIDIA examples (P3509-A01)
I have flashed Ubuntu 20.04 JetPack 5.x onto it. The power logic seems to work as jetson seems to boot up normally. As I copied the Module Power ON/OFF logic from P3449_B01 carrier board. Always enabling Auto Power
I haver another carrier which i previously used, and currently for testing purposes the RTSO-6002-V3.2
Product Manual for RTSO-6002.pdf (1.4 MB)
When I connect my computer with a microusb to the RTSO-6002-V3.2 carrierboard then i can see that my computer has detected a new device. In addition if i use Debug uart RX and TX to see what is going on at the kernel level, then i can see that upon inserting USB Jetson detects it or basically does something.
When I connect it to my carrierboard then the logic seems to work GPIO 87 USB0_VBUS_Jetson is at 1.8V untill i connect the USB, when I connect the usb to my carrierboard then GPIO 87 USB0_VBUS_Jetson is grounded, at 0V. When measuring N and P datalines with multimeter then P upon being connected is usually at around 100mV and N jumps between 1V-3V so it seems that something is happening.
When I use Debug UART RX and TX to see what is going on then when connecting the USB absolutely nothing new is logged, not even an error message.
When routing i used altiums impedence calculator and diff pair settings to get the Trace impedance: Diff pair to 90 ohms, and their differences in length under 7.5 ps. The total lenght of one trace is 94.66 mm which is smaller than the maximum of 150mm.
It is a 6 layer board where it goes Signal - GND - PWR - SIGN - GND - Signal. The Micro USB is entirely on the top layer.
Coming back to power logic there doesn’t seem to be any issues because my carrierboard behaves very closely RTSO-6002-V3.2 where the consuption at 5V goes from 600mA to 1.3A to backto 600mA with a lot of jumps but stabilizing at that point.
Measuring the TVS diodes they seems to work fine, doesn’t seem like they’re broken. Visually it doesn’t seem like N or P datalines have been damaged.
Have I understood correctly that Jetson detects that it has been connected to a device if GPIO 87 (USB_VBUS_EN0 from pinmux table) is grounded. Then it should send out information to the device and everything should be working.
The RTC 3V3 coin battery seems to work aswell. The power pins i have left floating are PIN 178 MOD_SLEEP, PIN 210 CLK_32K_OUT, PIN 240 SLEEP/WAKE. Because the only functionalities I need are USB 3.0, UART, SPI, CAN, USB 2.0.
Is there any other way I could test what could be the issue?
