RAD Data comm ASMI-450 operation manual Test Functions

Diagnostics

	5.3 Test Functions
Test Functions	The ASMi-450 supports the following types of test functions:
	∙ Local loopback on the user's port of the local ASMi-450 (LOOP LOCAL
	PORT).
	∙ Remote loopback on the user's port of the remote ASMi-450 (LOOP REM
	REM PORT).
	The loopbacks are not available for an ASMi-450 with the Ethernet interface.
	The user-controlled test functions are accessed from the TEST OPTIONS menu.
	In addition, when the internal jumpers ALB and RLB are set to EN (see Section
	2-4 for detailed instructions), the LOOP LOCAL PORT and LOOP REM REM
	PORT loopbacks, respectively, can also be enabled via the corresponding
	CCITT Rec. V.52 pins in the DCE connector.
	The available test functions are described in the following paragraphs. The test
	functions are identified by the designation displayed by the ASMi-450.
	LOOP LOCAL PORT
	When activated, the local user's port loopback returns the signal received from
	the user's DTE, after passing through the user's port interface of the ASMi-450.
	The local loopback is formed by connecting the transmit signal, provided by the
	user's port interface to the processing circuits, to the input of the receive path of
	the user's port interface. The test signal is provided by the DTE connected to the
	ASMi-450, that must receive its own transmission without errors while the
	loopback is activated. During the loopback, the local ASMi-450 continues
	sending the user's data to the link.
	Figure 5-1 shows a typical local user's port loopback.
	This test is generally used to check the connections between the DTE and the
	ASMi-450.

	LOCAL ASMi-450
User			HDSL Line
		Processing
Interface			Interface

HDSL Line

	REMOTE ASMi-450
HDSL Line	Processing	User
Interface		Interface

Figure 5-A. LOOP LOCAL PORT Loopback

5-6 ASMi-450 Installation and Operation Manual