After getting a good look at the
Cab.Link CLS-D4E2WX1
from the outside it was time to void the warranty and open the box. The
two screws are hiding under the little rubber feet at the front side and
after removing those two screws the case opens with a bit of jiggling.
This device has an external 12 volt 1 ampere power supply.
Chips found on the board:
Qualcomm QCA7411L-AL3C - Homeplug AV / IEEE 1901 the ethernet over cable interface I guess
I also see an extra board (leftside of the picture, blue) where the u.fl cable
to the wifi antenna starts. It has a few larger chips but those have a label
over them. I guess one of them must be the CPU because I haven't seen a chip
with that function yet.
The makers of the Cab.Link CLS-D4E2WX1 were kind enough to include 4 pins
labeled J30 (bottom left of the picture) which are a very obvious candidate for
being the uart port. Again the process for find GND, TX, RX and Vcc was done
and the right pins found. With the board in front and the J30 readable the pins
are from left to right TX, RX, GND and 3.3 volt. I name the TX and RX pins from
the view of the system, so I see data transmitted on TX and I send data to RX.
The uart voltage is 3.3 volt. The uart speed turned out to be 115200 bps in
this device. Connecting a terminal program via a serial interface gives bootup
messages, with U-Boot
Linux version 2.6.31 (root@ubuntu) (gcc version 4.3.3 (GCC) ) #3 Fri Nov 29 13:24:10 CST 2013
The system is clearly based on OpenWrt which the telnet interface also
confirms. The web interface avoids mentioning this.
After boot pressing enter on the serial interface gives a welcome message
and a root prompt:
koos@kernighan:~$ telnet 192.168.1.1
Trying 192.168.1.1...
Connected to 192.168.1.1.
Escape character is '^]'.
WARNING: telnet is a security risk
OpenWrt login: root
Password:
BusyBox v1.15.3 (2013-11-21 11:54:18 CST) built-in shell (ash)
Enter 'help' for a list of built-in commands.
______ ______ _______ .______ ______ __ _______
/ | / || \ | _ \ / __ \ | | | \
| ,----'| ,----'| .--. || |_) | | | | | | | | .--. |
| | | | | | | || / | | | | | | | | | |
| `----.| `----.| '--' || |\ \----.| `--' | | | | '--' |
\______| \______||_______/ | _| `._____| \______/ |__| |_______/
Copyright (c) 2013 ITTIM, Inc. ------------------------------------
* All Rights Reserved.
* ITTIM Confidential and Proprietary.
-------------------------------------------------------------------
root@ccdroid:~#
Having access also means I can ask for what kind of CPU is in there:
root@ccdroid:/# cat /proc/cpuinfo
system type : Atheros AR9330 (Hornet)
processor : 0
cpu model : MIPS 24Kc V7.4
BogoMIPS : 266.24
wait instruction : yes
microsecond timers : yes
tlb_entries : 16
extra interrupt vector : yes
hardware watchpoint : yes, count: 4, address/irw mask: [0x0004, 0x0890, 0x0020, 0x0ff8]
ASEs implemented : mips16
shadow register sets : 1
core : 0
VCED exceptions : not available
VCEI exceptions : not available
root@ccdroid:/#
The Atheros AR9330 is a complete 'System on a Chip' (SoC) with a MIPS CPU,
802.11n wifi. According to the information I can find this chip also has a 4
port ethernet switch, so I wonder why the router also has a Realtek RTL8306E
chip. Maybe to connect to the HomePlug interface chip?
There is also another weird thing: the Winbond W9412G6KH-5 memory chip is on
the main board, the little blue board seems to have the CPU. This means all
communication with the RAM goes over the bridge between the CPU board and the
main board.
From the boot messages I can also see there is a flash memory chip, but I
don't know the type yet. Trying to read the markings from the chips is
hard with some of the chip, including the chip I see as a candidate for
being a flash eprom. The boot messages say something about the flash
memory:
Manufacturer 0xc8 is 'ESMT' according to some searching, Elite
Semiconductor Memory Technology in full. But that's not helping me
identify the flash chip.
Searching for Flash Manuf Id 0xc8, DeviceId0 0x40, DeviceId1 0x17
finds this is also used in the TP-Link Archer C60 version 1 according to
Tp link archer c60 bad magic number - Installing and Using OpenWrt - OpenWrt Forum
and according to [OpenWrt Wiki] TP-Link Archer C60 this is a W25Q64 which turns out to
be a winbond W25Q64 with 8 pins, so probably the 8-pin chip I suspected.
Browsing around on the filesystem finds /usr/sbin/wshaper.htb which
is my old friend The Wonder Shaper.
I was again interested whether I could find any mention of plc on the
filesystem, but I found absolutely nothing.