Initiates and terminates self test pattern generation and detection (active diagnostic tests) on the DSU channel. When this object is set to other than sendNoCode(1), an active diagnostic test is initiated, using the test pattern supplied . When this object is set to sendNoCode(1), the active diagnostic test is terminated. When read, value sendNoCode(1) indicates there are no active diagnostic tests currently running on the channel. The value sendQRSpattern(2) indicates that a QRS test is running on the channel. The value send511Pattern(3) indicates that a 511 test is running on the channel. The value send3in24Pattern(4) indicates that a 3:24 test is running on the channel. The value send2047Pattern(5) indicates that a 2047 test is running on the channel. The value sendProgPattern(6) indicates that a user programmable pattern test is running on the channel. The value sendProgPattern(6) and the object gdcDsuChannelProgPattern work together. GdcDsuChannelProgPattern defines the 16 bit user programmable pattern for the programmable pattern test. The values send511PatternWithLL(7), send511PatternWithRDL(8), send2047PatternWithLL(9), send2047PatternWithRDL(10) indicate that the given pattern test is running in conjunction with a local loop (LL) or remote digital loop (RDL). gdcDsuChannelLoopbackConfig is updated to indicate this as well. When one of these tests are running, and this variable is set to sendNoCode(1), both the pattern and the loopback are terminated. However, if gdcDsuChannelLoopbackConfig is set to noLoop(1), only the loopback portion is terminated. This object, gdcDsuChannelTestResults, and gdcDsuChannelTestStatus work together as follows: When this object is set to initiate an active diagnostic test, gdcDsuTestResults is initialized to 0 and gdcDsuChannelTestStatus is initialized to testRunning(1). When the test is terminated, the value of gdcDsuChannelTestStatus reflects testComplete(3). gdcDsuChannelTestResults contains the count of bit errors detected during the test.