Hi all,
What PCI lanes do the two 22x80mm M.2 slots on the bottom of the BitBrick K1 have - is it each one PCIe v2 lane, or each has two PCIe v2 lanes?
And, what PCI lanes does the small M2 slot on the top of the SBC have, one PCIe v2?
Thanks
Each of the M.2 slots at the bottom has one PCIe v2 lanes, and the M.2 slot at the top uses SDIO.
@admin Aha so that means each of those two M.2 slots have 4gbit = 500MB/sec bandwidth. Thank you for clarifying.
Can you remind, the K1 SoC, how many PCIe lanes does it have in total, and what does the BitBrick K1 SBC use the other lanes for?
Also, just curious, what 22x42mm M.2 hardware exists that accepts the SDIO protocol? I have never heard of it. Can you give some example.
Update: It’s special WIFI cards that are based on SDIO and don’t use USB or PCI.
(I see the documentation page Bit-Brick K1 | Bit-Brick but find it a bit hard to read.)
The K1 SoC has a total of 3 PCIe lanes. The K1 SBC uses 2 PCIe lanes for the M.2 M-KEY interface, and multiplexes 1 PCIe lane for the USB3.0 interface.
@admin Wait, what interface does the M.2 E-key 22x30mm slot on the top have?
On the bottom, do you mean that each of the M.2 M 22x80mm slots only have 1 PCI v2 lane, each 500MB/sec (4gbps)?
I understand the SpaceMIT K1 have 2 + 2 + 1 = 5 PCIe v2 lanes in total. I.e. three PCIe devices are supported in total.
I thought each of the TWO M.2 22x80mm slots on the bottom have TWO lanes each (so FOUR in total), and the individual 1 lane is used for USB 3, and the M.2 22x30mm E-key slot on the top is connected to SDIO?
Can you please clarify.
Ref. K1 – BIT-BRICK
Also ref. K1 M.2 Interface Description | Bit-Brick . Here, the 2230 E-key slot is called “M.2 SLOT 0”, and it says the following, which means there are ZERO PCIe lanes going to it:
The other M.2 SLOT 0 is the interface definition of KEY-E, with a length of 2230, which is mainly used to support various wireless modules. Since the processor only has three USB interfaces, the USB interface is not reserved for SLOT 0, and the PCIE interface compatible with NGFF is also removed, so modules with USB and PCIE interface definitions are not supported.
This page does not have any information about the two M.2 22x80mm M-key slots, which it calls “M.2 SLOT 1” and “M.2 SLOT 2”.
Your explanation is correct.
“I understand the SpaceMIT K1 have 2 + 2 + 1 = 5 PCIe v2 lanes in total. I.e. three PCIe devices are supported in total.
I thought each of the TWO M.2 22x80mm slots on the bottom have TWO lanes each (so FOUR in total), and the individual 1 lane is used for USB 3, and the M.2 22x30mm E-key slot on the top is connected to SDIO?”
I made a mistake in my response earlier, and I apologize for that!
1 个赞
Awesome. Ok this means each of BitBrick’s 22x80mm M.2 slots each have 2x PCIe v2 lanes, that is 1000MB/second or 8 gigabit per second bandwidth per M.2 slot.
(Each has 2 PCIe lanes x 4 gigabit per second or 500MB/second bandwidth per PCIe lane.)
That’s perfect. Thanks.