DUL 20 » History » Revision 14
Revision 13 (laforge, 11/03/2020 03:24 PM) → Revision 14/15 (laforge, 11/03/2020 03:25 PM)
h1. DUL 20
DUL is a Digital Unit for LTE. It contains the eNodeB function down to the baseband processing.
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h2. Connectors
h3. PWR
48V DC connector. The negative rail is towards the edge of the unit. Also seems to power up fine at 36V
The connectory type is https://www.te.com/usa-en/product-1982299-3.html with associated crimp contacts.
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h3. GPS (RJ45)
Connection for an Ericsson GPS module, contains 1PPS and UART signals
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h3. EC (RJ45)
Environment Control? Probably some RS-485 to control fans, power management, UPS, ...
h3. AUX (RJ45)
?
h3. LMT A (RJ45)
A RS-232 on RJ45 for Local Maintenane use. IT provides access to COLI (COmmand LIne).
The pinout is shown below. Please note it is *different from RBS3000!*, but identical to that of the [[DUG 20]]
|_.RJ45|_.DB9|_.Name|
|1|5|GND|
|2|3|TXD (of PC)|
|3|2|RXD (of PC)|
The [default?] baud rate settings are 9600 8N1.
This port provides RS-232 access to the [[OSE]] shell
h3. LMT B (RJ45)
_Site LAN_ Ethernet, for adminstrative purpose
This is the interface used for configuration of the DUL during installation.
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h3. TN A (RJ45)
_Transmission_ Ethernet, i.e. the back-haul interface for S1. RJ-45
h3. TN B (SFP)
_Transmission_ Ethernet for optical back-haul. Can use normal SFP modules.
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h3. IDL (HSIO)
Inter-DU-Link for cross-connecting multiple DU.
h3. RI A..F (SFP)
Radio Interface (CPRI) using either SFP transceivers for RRU connection or copper interconnect cables for RU.
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h2. Overview Pictures
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h2. Accessing it
h3. SSH via LMT-B
It appears the DUL will always respond to 169.254.1.10/16, no matter what kind of real/other IP address has been set.
You have to use the following SSH config to speak the ancient cipher/key-exchange:
<pre>
Host dul
HostName 169.254.1.10
KexAlgorithms diffie-hellman-group1-sha1
Ciphers 3des-cbc
</pre>
and then log in as the 'rbs' user with 'rbs' password.
h2. Mass Storage
The DUL20 has an internal CompactFlash slot. The slot is only accessible when disassembling the unit, removing the circuit board from the enclosure.
It uses 2GB CFlash cards with no known partition table / format.
