Rainbow Electronics DS3170 - Manual (Page 51)

DS3170 DS3/E3 Single-Chip Transceiver
51 of 233
8 INITIALIZATION AND CONFIGURATION
STEP 1: Check Device ID Code.
Before any testing can be done, the device ID code, which is stored in GL.IDR, shoud be checked against the
device ID code shown below to ensure correct device is being used.
Current device ID codes is:
o DS3170 rev 1.0: 004Fh
STEP 2: Initialize the Device.
Before configuring for operation, make sure the device is in a known condition with all registers set to their default
value by initiating a Global Reset. (See Section
9.3 .) A Global Reset can be initiated via the RST pin or by the
Global Reset bit (GL.CR1.RST). A Port Reset is not necessary since the global reset includes a reset of the port to
its default values.
STEP 3: Clear the Reset.
It is necessary to clear the RST bit to begin normal operation.
After clearing the RST bit, the device is configured for default mode.
Default mode:
Framer: C-bit DS3
LIU: Disabled
STEP 4: Clear the Data Path Resets and the Port Power-Down bit.
The default value of the Data Path Resets is one, which keeps the internal logic in the reset status. The user
needs to clear the following bits:
GL.CR1.RSTDP = 0
PORT.CR1.RSTDP = 0
PORT.CR1.PD = 0
STEP 5: Configure the CLAD
If using the LIU, configure the CLAD (which supplies the clock to the Receive LIU) via the CLAD bits in
the
GL.CR2 register.
Note: The user must supply a DS3, E3, STS-1, 77.76 MHz, or 19.44 MHz clock to the REFCLK pin.
STEP 6: Select the clock source for the transmitter.
Loop Time (use the receive clock): Set PORT.CR3 .LOOPT = 1
CLAD Source: Set PORT.CR3 .CLADC = 0
TCLKI Source: Set PORT.CR3 .CLADC = 1
If using the CLAD, properly configure the CLAD by setting the CLAD bits in GL.CR2.
STEP 7: Configure the Framing Mode and the Line Mode..
PORT.CR2.LM[2:0] = 011 (LIU on, JA in rx side) or another setting. See Table 9-26
PORT.CR2.FM[2:0] set to correct mode. See Table 9-25.
STEP 8: Disable Payload AIS (downstream AIS) and Line AIS
PORT.CR1.PAIS[2:0] = 111
PORT.CR1.LAIS[1:0] = 11
STEP 9: Enable the port (for non-LIU modes)
PORT.CR2.TLEN = 1