4RF Aprisa XE User Manual page 167

Cross Connections | 165
QJET Spare CAS Bit Control
The Aprisa XE can currently provide E1 CAS to DFXS circuits using the 1 bit '4 wire compatible' signalling
mode (uses the CAS A bit) but to enable some exchange DTIs to operate, the state of the spare CAS bits
sent to the exchange must be preset.
The available CAS bits can be preset to High (1) or Low (0) for the QJET framed modes of E1 - PCM30,
E1 - PCM30C, T1 SF - DMS and T1 ESF – DMS for all timeslots of the port.
To preset the spare CAS bits:
Right click on the CAS bit required to be set.
Select 'Set High CAS Bit x' or 'Set Low CAS Bit x'.
The screen shot shows the standard configuration where the DFXS signalling using 1 bit '4 wire compatible'
signalling mode is mapped to the QJET CAS A bit and the 'spare' CAS bits are preset to the standard 1 bit
protocol spare bit pattern of BCD = 101.