Hi all, I’m working on a custom motherboard/carrier board for the NVIDIA Jetson Nano and I’m using the Arducam M23390H08 (B251) camera module with the IMX477 sensor. I’m a bit confused about the CSI lane count. The Arducam datasheet for the M23390H08 says the interface is 2-lane CSI. But the IMX477 sensor datasheet says the sensor supports 4 lanes. On top of that, the Arducam datasheet pinout for the 22-pole connector shows 2 additional CSI lanes, so 4 total. Are those extra lanes actually connected to the IMX477 and usable, or is there no real benefit from them?
Welcome to the forum. That’s a fair question, the two datasheets do seem to point in different directions. Before I dig into it, can you confirm the exact setup you’re working with? I’m assuming Jetson Nano SBC plus the M23390H08 (B251), and are you using the 22-pin FPC cable with the 22-pole connector?
Right, the environment is:
- NVIDIA Jetson Nano SBC
- Arducam M23390H08 (B251) camera with IMX477 sensor
- 22-pin FPC cable / 22-pole connector
Related to that: if I use a 22p FPC cable, would that let me run all 4 lanes? Also, can you confirm the I2C address for camera configuration is 0x34/0x35?
Thanks, that matches what I needed. I checked this against the module design. The key point is that the M23390H08 does not support 4-lane operation. The IMX477 sensor itself is capable of four-lane data transmission, but only two lanes are actually available on this module because of the connector limitation. So even if you connect it with a 22p FPC cable, you cannot use 4 lanes.
Okay, so the sensor supports 4 lanes but the module/connector only exposes 2 usable lanes, meaning the extra pins are not a real path for 4-lane data. So should I configure it strictly as 2-lane, and is 0x34/0x35 still the correct I2C address for configuration?
Correct, use only 2-lane CSI mode and do not attempt to configure the M23390H08 for 4-lane operation. And yes, configure the camera using I2C address 0x34/0x35. To sum it up: the IMX477 supports four-lane data transmission, but the Arducam M23390H08 is limited to two lanes due to the connector limitation, so 4 lanes cannot be used even with a 22p FPC cable. Stick with 2-lane CSI mode.