PSB2115HV1.2 Lantiq, PSB2115HV1.2 Datasheet - Page 117

• Manufacturer Part Number: PSB2115HV1.2
• Manufacturer: Lantiq

Specifications of PSB2115HV1.2

• Lead Free Status / Rohs Status: Supplier Unconfirmed

PSB 2115
PSF 2115
Functional Description
®
2.7.2
IOM
-2 Interface Connections
Output Driver Selection
FSC and DCL are push pull outputs (TE mode).
The output type of the IOM datalines is selectable via bit CONF:ODS. ODS set to 0
selects open drain (reset value) and ODS set to 1 selects push pull outputs.
Normally the IOM-2 interface is operated in the "open drain" mode (ODS=0) in order to
take advantage of the bus capability. In this case pull-up resistors (1 k
– 5 k ) are
required on DU and DD.
In push pull mode (ODS=1) DU and DD are also high impedant outside the active
timeslot the IPAC is programmed to.
IOM-2 OFF Function
The IOM-2 interface can be switched off for external devices via bit IOF in the CONF
register. The output lines can be set to tristate if bit CONF:IOF is set to 1, so DU/DD,
FSC, DCL and SDS are high impedant, else the selection in ODS determines the output
driver characteristic (push pull or open drain).
In Non-TE mode the clocks FSC and DCL are not switched off from the IOM-2 interface
for IOF=1 but remain as input, however the datalines DU and DD are tristate.
IOM-2 Direction Control
The direction of the IOM-2 data lines depends on the mode selected by pins MODE0 and
MODE1/EAW for the Layer 1 block and by the configuration of CCR2:SOC for the B-
channel HDLC controller and SPCR:SDL for the D-channel controller (see figure 55).
According to the mode selection (see chapter 2.7.1) the layer 1 controller always carries
data from the subscriber to the central office on DU and data in the opposite direction on
DD.
For test applications, the direction of DU and DD can be reversed separately for the B-
channel controller and for the layer 2 block. For normal operation both bits CCR2:SOC
and SPCR:SDL should be set to 0 in TE and LT-T mode and should be set to 1 in LT-S
mode.
Semiconductor Group
117
11.97