# Error cause values

The following table lists the valid error code values for the Acu_err_in_cause macro in ACU_ERR_IN messages. These values are defined in isdnacu.h.

Cause code | Description
--- | ---
ACUER_PRIMITIVE_CODE | Unknown primitive code.
ACUER_PARAM_VAL | Invalid parameter.
ACUER_MANDATORY_PARAM_MISSING | Mandatory parameter missing.
ACUER_PARAM_TYPE | Incorrect parameter type.
ACUER_PARAM_LGTH | Incorrect parameter length.
ACUER_UNEXPECTED_PRIMITIVE | Unexpected primitive.
ACUER_PRIMITIVE_NOT_IMPLEMENTED | SSDU primitive not implemented.
ACUER_NO_TIMER_AVAILABLE | No more space to allocate new timer cells.
ACUER_CONGESTION | Resource congestion.