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PEB 20321
PEF 20321
Host Memory Organization
Data Sheet
277
2001-02-14
For test purposes, four different loops can be switched at the serial interface using the
following coding of the bit fields LOC, LOOP, LOOPI:
LOC
LOOP
LOOPI
Interpretation
0
0
0
no loop
0
0
1
complete internal loop
0
1
0
complete external loop
0
1
1
switch loops off
1
0
0
not allowed
1
0
1
channelwise internal loop
1
1
0
channelwise external loop
1
1
1
not allowed
The loops have the following functions:
–
Complete external loop
The serial data input is physically mirrored back to the serial data output. The time and
strobe signals for receive and transmit direction must be identical.
–
Complete internal loop
The serial data output is physically mirrored back to the serial data input. The data on
the external input line are ignored. The logical channels have to be programmed
identically. The time and strobe signals for receive and transmit direction must be
identical.
–
Channelwise external loop
One single logical channel is mirrored logically from serial data input to serial data
output. The other channels are not affected by this operation. The data rate for this
single logical channel must be identical for receive and transmit direction.
–
Channelwise internal loop
One single logical channel is mirrored logically from serial data output to serial data
input. The other channels are not affected by this operation. The data rate for this
single logical channel must be identical for receive and transmit direction.
All loops of the MUNICH32X are under complete software control. Loops can be closed
and opened via software. Note that a more detailed description of the test loops will be
provided later in the Application Notes section.
Handling of the Loops
1. Switch on loops:
RES = IN = ICO =
‘
0
’
LOC, LOOP, LOOPI
PCM, MFL
CHANNEL NUMBER
determine the selected loop type
do not change the previous values
in case of channelwise loops use the selected
channel number;
in case of complete loops use channel number of an
active channel.