Can Orin NX module support two M.2 Key M slots?

We are designing a custom carrier board for Orin NX module using NVIDIA’s Xavier NX carrier board as a reference. Please clarify the following details.

  1. Orin NX has 1x4(PCIe0), 1x1(PCIe1) and 1x2(PCIe2) GEN4 PCIe interface, does it support two M.2 key M slots for SSD memory? one over 4 lane(PCIe0) and other one over 2 lane(PCIe2) and also M.2 Key E over 1 lane(PCIe1) for WiFi/BT module.
  2. Is it possible to add SD card or eMMC as alternate memory option for Orin NX?

Regards,
Natesan S

Please refer to the Orin NX Design Guide in DLC only for custom PCIe and other port design.

Yes, I referred Orin NX design guide too. My question is whether Orin NX can support two M.2 Key M slots to connect SSD? Orin NX has 1x4(PCIe0) and 1x2(PCIe2) GEN4 PCIe interface. I couldn’t find any details about this in design guide. Kindly confirm.

Yes as said in DS: Supports External Storage (NVMe) via x2 or x4 PCIe.

Any inputs to to add SD card or eMMC as an alternate memory option?

It is not supported.

We are using PCIe2(x2) of ORIN NX for second NVMe SSD over M.2 Key M slot. Kindly clarify the below points.

  1. Shall I leave PET2P/N, PER2P/N, PET3P/N and PER3P/N of M2 Key M slot unconnected?
  2. Also, both the M.2 Key M slots share the same PCIe wake pin, is it okay?
  3. What if both the M.2 Key M share the same SUSCLK(32KHz) source? or it should be seperate?
  4. Is it okay if both M.2 Key M share the same I2C of ORIN NX?
  5. Can M2Malert# pin be connected to any GPIO?

Regards,
Natesan S

Please clarify the doubts.

SD/EMMC can be connected via USB.
Have a look at Microchip USB2642. This does support EMMC even with 8 data lines.

1 Like

Thank you, let me have a look at it.

Hello @Trumany

Could you please clarify the below points?

  1. Shall I leave PET2P/N, PER2P/N, PET3P/N and PER3P/N of M2 Key M slot nconnected?
  2. Also, both the M.2 Key M slots share the same PCIe wake pin, is it okay?
  3. What if both the M.2 Key M share the same SUSCLK(32KHz) source? or it should be seperate?
  4. Is it okay if both M.2 Key M share the same I2C of ORIN NX?
  5. Can M2Malert# pin be connected to any GPIO?

Regards,
Natesan S

  1. Yes
  2. Yes
  3. Yes, sharing the clock signal is okay.
  4. It depends on the device in the slot. You could end up with the devices in both slots having the same i2c address. A I2C Multiplexer like PCA9542A with avoid this problem.
  5. I’ve never used that signal, so I don’t know.

Regards,
Frank

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Hello @fchk

Thank you for the details.

I read that I2C is optional for NVMe, is it so? If yes, shall I leave I2C of both the M.2 Key M unconnected? Please clarify.

Regards,
Natesan S

Yes, I2C is not needed for most devices like SSDs, network interfaces or framegrabbers.

I strongly recommend getting both the original PCI Express Base Specification and the original PCI Express M.2 Specification from the PCI SIG.

Frank

Is this straightforward? Or do I need to make changes to the bootloader(Would like instructions on that if required.).

Thanks!

The assembly consisting of an USB-SD/EMMC bridge and SD/EMCC media provides a standard USB 2.0 Mass Storage interface. If an USB stick works this assembly will work as well, since it basically is an USB Stick. Should work in any system (PC,…).

fchk

@Sivam_Natesan what are the current questions here?

Hello

We are using PCIe2(x2) of ORIN NX for second NVMe SSD over M.2 Key M slot. Kindly clarify the below points.

  1. Shall I leave PET2P/N, PER2P/N, PET3P/N and PER3P/N of M2 Key M slot unconnected?
  2. Also, both the M.2 Key M slots share the same PCIe wake pin, is it okay?
  3. What if both the M.2 Key M share the same SUSCLK(32KHz) source? or it should be seperate?
  4. Is it okay if both M.2 Key M share the same I2C of ORIN NX?
  5. Can M2Malert# pin be connected to any GPIO?

Regards,
Natesan S