Author Topic: Enabling 911/112  (Read 5030 times)


  • Newbie
  • *
  • Posts: 5
    • View Profile
Enabling 911/112
« on: August 03, 2015, 10:46:38 AM »
Hi again,

I had previoously posted this question in the "other Yate server issues" section of the forum and got no replies.
Perhaps I should have posted the question here since this seems to be the proper YateBTS section.
Hopefully someone besides myself has tried to enable emergency services functionality and can point me in the right direction in the code.


Hi all,

I've searched through the yatebts code trying to figure out where I can change the parameter that is broadcast and tells registering cell phones that emergency calls are disabled (that's the message I get on my cell phone everytime I associate to the YateBTS GSM network).

I found the equivalent parameter in OpenBTS from here

# Access class flags.
# This is the RAW parameter sent on the BCCH.
# See GSM 04.08 for encoding.
# Set to 0 to allow full access.
# Set to 0x0400 to indicate no support for emergency calls.

My question is where can I find the equivalent parameter in YateBTS? Is there any documentation out there regarding configuring emergency call support?



  • Newbie
  • *
  • Posts: 14
    • View Profile
Re: Enabling 911/112
« Reply #1 on: August 30, 2015, 06:12:26 PM »
Access flags are set in the source code, they can be altered by editing file: GSML3RRElements.h and then re-compiling the code.

Not sure why YateBTS removed this when OpenBTS has it as an option....

/** RACH Control Parameters GSM 04.08 */
/** Default constructor parameters allows all access. */
      // Values ditected by imnplementation are hard-coded.
      // Configurable values.
      mMaxRetrans = gConfig.getNum("GSM.RACH.MaxRetrans");
      mTxInteger = gConfig.getNum("GSM.RACH.TxInteger");
      mAC = 0x0400; //NO EMERGENCY SERVICE - kurtis

Set the bit in bold to 0x0000

Once changed the network will now advertise that it CAN handle emergency calls (so make sure it really can)