BusinessPhone Communication Platform 4.0
Commands > Commands 1000...1999

## 1920
CRC4 check

The command is used to define the mode of Cyclic Redundancy Check (CRC4) for ISDN Primary Rate Access (PRA). CRC-4 procedure for multiframe alignment and bit error monitoring is designed to supervise if frame alignment has been lost and if the bit error rate is within a specified range.

There are two modes of operation:

Automatic |  | The equipment adapts itself to the operation of the network. This will be used in most markets. |
Permanently |  | This is used qhen the network does not support the automatic function. |

Value = |  | 0 |  | Automatic selection (by layer 1) |
|  | 1 |  | CRC4 procedure permanently enabled |
|  | 2 |  | CRC4 procedure permanently disabled |
|  | 3 |  | Default (use market dependent parameter) |

Minimum required authority level from telephone: No

Accessible via BMS: Yes

Revision: A © Ericsson Enterprise 2003