Nvidia Jetson TX2 Development Kit

Question 1: After I power on the Jetson TX2, I press the Power Switch (S4), CR5 turns off immediately after the red light, and after a few seconds of long pressing S4, it can boot normally. Is this normal?
Question 2: In the above question, how to shut down (uninterrupted power) when the machine is turned on? Will direct power-off and shutdown cause problems with the development board?

Assuming this is the dev kit, from the user guide, page 6, interface details:

  • “[CR5] Red LED indicates when main power supply is connected and active”

CR5 should always be on if power is connected and available to the module, even if the unit is otherwise not running.

S4, if “tapped”, should start power up on a unit which is otherwise not running. If the unit is already running, then holding S4 (I am guessing between 5 and 10 seconds) would cause power off, but CR5 would still be lit. A brief touch of S4, or holding S4 for a second or two, should not differ in result.

The answer to forcing power off (which is not proper shutdown and will need filesystem recovery, probably through journal replay) is to hold S4 for about 10 seconds. The average PC takes about 5 seconds of holding down the power button, but the chip in the Jetson takes a bit longer.

Hardware will not be damaged by holding the power button or unplugging power (unless unplug causes a voltage spike). However, the filesystem will at minimum lose data. Anything which was written, but not committed, would at minimum be erased through ext4 journal replay. If the journal is not large enough (for example, if too much data was not flushed for a journal of a given size), then actual corruption occurs, and fsck.ext4 would be required (which loses even more content). If there was a lot of write activity going on, then conceivably even fsck.ext4 would fail (there would have to be a lot of unwritten disk for that to happen). Jetsons are like any other computer, and should be shut down correctly rather than having power cut (either by power loss or holding the power button down).

Thanks,The problem is basically solved. But,
CR5 does not light up after power-on, and CR5 does not light up after turning off (press and hold S4 for about 10 seconds), is this normal?

My carrier board is fairly old (from the first batch of TX2s), and my carrier has this light on at all times if power is delivered to the barrel connector. If the specification did not change, then CR5 turning off is a hardware failure. I don’t know that my carrier is the same as yours, but I suspect it is, and thus I suspect there is a hardware issue with CR5 on yours not lighting.

One thing I recommend doing is to test the voltage from your power supply while it is connected to the dev kit. If the voltage were to drop on the power supply, then the issue would likely be with power delivery (unless something shorted on the Jetson).

Hopefully someone from NVIDIA can confirm if there are any TX2 dev kits where CR5 does not light when there is power to the barrel connector.

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CR5 should be always ON when 19V plug in as you can see in P2597 schematic. Do you mean the CR5 on your board won’t be ON anyway? If so, there might be something related broken.

This problem is still unresolved, but it seems that there is no impact.

are you using the default devkit power source power supply?