AR300M PCIE port

The AR300M has a non standard PCIE connector that was originally intended for the 5G card. Is it possible to use this port to get an extra internal USB port instead? I have been searching online and i could not find any hardware mods for these routers.

I don’t think so. It is only for pcie.

If you need internal USB, check AR750S.

Yes i understand, but there are many PCIE to USB 2.0 cards in the market, i am just trying to figure out the wiring to get one of these cards working. The reason i want to do this with the AR300M instead of a 750s is

a) because i own one and
b) because of the external 2.4ghz antennas in the AR300M-ext

I saw the pictures of the 5G addon card in the FCC site and the card seems to be connected not only to the PCIE slot but also to the I2C GPIO pins.

Need to check the specs of PCIe to USB 2.0 cards. They are PCIe to USB, not USB to PCIe.

Never try something like that.

This is what i had in mind

I just trying to figure out what lines from the header go to which pin. PCI Express connector has 18 pins with 2 sides, so some of the pins will be missing but I don´t need the 36 pins to get a USB out. I am just trying to figure out if the pins used for the above card are available in the Header.

PCI Express 1.0 Pinout according to Wikipedia

Pin Side B Side A
1 +12 V PRSNT1#
2 +12 V +12 V
3 +12 V +12 V
4 Ground Ground
5 SMCLK TCK
6 SMDAT TDI
7 Ground TDO
8 +3.3 V TMS
9 TRST# +3.3 V
10 +3.3 V aux +3.3 V
11 WAKE# PERST#
Key notch
12 RSVD Ground
13 Ground REFCLK+
14 HSOp(0) REFCLK−
15 HSOn(0) Ground
16 Ground HSIp(0)
17 PRSNT2# HSIn(0)
18 Ground Ground

PCI Header according to AR300M docs

Pin Desc PCIE pin
1 GND Ok, this is ground so Pin 4AB 12A 15A and 18AB
2 RST Perhaps pin 1A
3 CK-P 13A?
4 CK-N 14A?
5 RX_P 16A?
6 RX_N 17A?
7 TX_N 15B?
8 TX_P 14B?
9 3V3 8B 9A 10A
10 GND same as 1

I will buy one of the half sized adaptors to test but they take forever to ship.

Checked the picture and seems it is only converting USB to PCIe physically by routing the pins, not electronically.

So this should not work in real PCIe interfaces.

For example, in MiFi there is PCIe LTE interface, but actually it is USB connection. You can use the board converting USB modem to PCIe modem then.

Wait- before I go cracking the case, does the AR-300M-Lite have this (mini-)PCI-E connector, too?

I have a few mini-PCIe LTE dongles around the house, I could use it for that? I’d have to figure out the SIM connector and the antennas and the software, but those may be doable (especially that last part).

Cannot remember if lite has the connector. I think it doesn’t.

In AR300M it is true PCIE interface Using 5x2 pins.
It do NOT work with PCIE modem which is actually using USB connection.

Gotcha. Storage (or the like) only, but you don’t think it’s in there anyway, so …

Hi, I just wanted to repeat the question 4 years later: are there any interesting mods using the PCI-E connector for anything? I couldn’t find anything on the net.

The QCA9531 datasheet says that there’s a “PCIE (1.1) root complex (RC) supporting a single-lane PCIE link at 2.5 Gbps”, and according to the pinout it appears that the AR300M is routing all of the pins to the connector.

It also shows up in the kernel:

[ 0.134774] PCI host bridge /ahb/pcie-controller@180c0000 ranges:
[ 0.152282] ar724x-pci 180c0000.pcie-controller: PCIe link is down
[ 0.176001] PCI host bridge to bus 0000:00
[ 0.180332] pci_bus 0000:00: root bus resource [mem 0x10000000-0x13ffffff]

So it would be nice to know of any ideas on how this could be used!

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