PXB4219E Datasheet, PDF (100/290 Pages) Infineon Technologies AG – Interworking Element for 8 E1/T1 Lines

IWE8, V3.4
PXB 4219E, PXB 4220E, PXB 4221E
Interface Description
5.1.3 Synchronous Modes (SYM)
In these modes, transmit and receive channels are synchronized. Therefore, they may
be used for synchronization of frame and multiframe based protocols, e.g. Frame based
SDT on E1-Lines.
Only one central clock, the external reference clock RFCLK, is used to clock the data on
the different ports. Two synchronous modes working at 2.048 MHz and 8.192 MHz for
E1lines are available. T1 is not supported.
For each of these modes a submode exists, providing global or port specific
synchronization.
If global synchronization of all transmit and receive channels is desired, bit “symn” in
“opmo” has to be deasserted. In this case FRMFB[0] is used for frame and multiframe
synchronization in receive and transmit direction of all ports.
Port specific frame and multiframe synchronization of transmit and receive channels is
enabled if bit “symn” in “opmo” is set. In this case frame and multiframe synchronization
in receive and transmit direction of each port is based on the corresponding FRMFB.
After reset all outputs and input/output ports of the framer interface are in tristate mode.
They will be enabled by setting bit “p_tx_act” of the corresponding “Port Configuration
Register” (“pcfN”, see Chapter 7.1).
5.1.3.1 Synchronous Mode at 2.048 MHz (SYM2)
In SYM2 mode the framer interface is clocked with a 2.048 MHz clock connected to
RFCLK. The mode is enabled by setting bit om = 11_B in “opmo”, see Chapter 7.24
All transmit and receive timeslots will be aligned to each other.
FRCLK[7:0]
FRDAT[7:0]
FRMFB[7:0]
Framer Receive Clock
Unused
Framer Receive Data
depending on bit “frri” in “opmo”
0=
FRDAT is sampled with the falling edge of RFCLK
1=
FRDAT is sampled with the rising edge of RFCLK
Framer Receive Multiframe Begin
Depending on bits p_ces in pcfN:
0=
Structured CES: A pulse on this pin designates the
first frame of a new multiframe
1=
Unstructured CES: Unused, no constant level
allowed
depending on bit “rfpp” in “opmo”:
Data Sheet
100
2003-01-20