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title: <center><i class="fa fa-edit"></i> Schema of main function (first part)</center>

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# <center><i class="fa fa-edit"></i> Schema of main function (first part)</center>
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[TOC]

### Schema (first part)
![](https://i.imgur.com/Pq1KxUx.png)

### Explanation of blocks

#### Initialisation of NR configuration block
At this block we have to start a background system, after that load configuration modules and the last thing is to set soft modem signal handler.
#### Getting information about AMF and NGAP


| AMF                     | NGAP                    |
| ----------------------- | ----------------------- 
|  Automatic Mains Failure|NG Application Protocol|
| AMF panels are designed to switch the electrical load of system from the normal supply to a standby supply, normally a generator, and then back when required. | Provides the control plane signalling between NG-RAN node and the Access and Mobility Management Function  |

#### Initialize a MSC-gen log

At this block we have to initialize a OPt, after that if PDCP uses a netlink, than we have to initialize a netlink. Then we have to write some info in log about HW (hard ware) and package version

#### Initialize UE PF PO and mutex lock
- **UE** - *user equipment*
- **PF** - *Paging Frame*
- **PO** - *Paging Occasion*
- **nFAPI** - *is implementation of the Small Cell Forum's network functional API or nFAPI for short. nFAPI defines a network protocol that is used to connect a Physical Network Function (PNF) running LTE Layer 1 to a Virtual Network Function (VNF) running LTE layer 2 and above.* 

Firstly we have to initialize a mutix function(pthread_mutex_init() function initialises the mutex referenced by mutex with attributes specified by attr), fill a block of memory with a particular value, initialises the condition variable and mutex referenced. 
If nFAPI gets mode, than we will see a message "NFAPI*** - mutex and cond created - will block shortly for completion of PNF connection"





