Adding support for MikroTik hAP ac3 LTE6 kit (D53GR_5HacD2HnD)

For Developers
45

Further findings with modem:

  1. it is now definitive that the modem by default goes into CFUN=4 ("fligh mode"). And mikrotik ROS moves the modem out from this state during bringup.

  2. By default the modem is in RNDIS state. In order to get proper IP the RNDIS interface needs to be set up as a DHCP client interface and extra AT commands needeD:

AT+ZGDCONT=5,"IP","internet",0
AT+ZGPCOAUTH=5,"","",0
AT+CFUN=1
AT+ZGACT=1,5

After this a restart of the RNDIS DHCP client will pass the IP issued by the mobile operator directly to the RNDIS interface:

image

Issuing a reset (AT+RESET) to the modem will move the RNDIS interface back to its internal IP state:

image

This is a pile of shite of course, as normally we don't want to deal with this, the modem should just boot to a default working state. But at least we know this is the situation presented by MikroTik.

MOD: searching for this issue I found that someone already find and fixed this issue for a different modem device with a similar Marvell chipset:

https://git.openwrt.org/?p=openwrt/openwrt.git;a=commitdiff;h=0a5f3b012669208f5454ebe4a1def16e5ab093dd

1 Like