Altigen AltiWare OE Version 4.6 Administration Manual page 476

CD Bits Handling is selected to "CD = 01". If all configurations are
correct, the status of trunk line should be shown as "OK."
Step 2: Data Link Layer
In the T1/E1 Configuration window, the Span type selection should be
E1 CAS. In the E1 R2 setting field, select the switch mode according to
your country.
B-2 AltiWare OE System Installation & Administration Manual