
Data Sheet
173
Rev. 1.2, 2006-01-26
QuadFALC
TM
PEF 22554 E
Functional Description T1/J1
Reporting and controlling of slips
Controlled by special signals generated by the receiver, the unipolar bit stream is converted into bit-parallel, time
slot serial data which is circularly written to the elastic buffer using internally generated Receive Route Clock
(RCLK).
Reading of stored data is controlled by the system clock sourced by SCLKR or by the receive jitter attenuator and
the synchronization pulse (SYPR) together with the programmed offset values for the receive time slot/clock slot
counters. After conversion into a serial data stream, the data is sent out on port RDO. If the receive buffer is
bypassed programming of the time slot offset is disabled and data is clocked off with RCLK instead of SCLKR.
The 24 received time slots (T1/J1) can be translated into the 32 system time slots (E1) in two different channel
translation modes controlled by FMR1.CTM (FMR1_T). Unequipped time slots are set to FF
In one frame or short buffer mode the delay through the receive buffer is reduced to an average delay of 96 or 48
bits respectively.
In bypass mode the time slot assigner is disabled. In this case SYPR programmed as input is ignored and the clock
provided on pin SCLKR is ignored. Clocking is done with RCLK.
Slips are performed in all buffer modes except the bypass mode. After a slip is detected the read pointer is
adjusted to one half of the current buffer size.
Table 48 gives an overview of the receive buffer operating modes (SIC1_T).
Table 47
Channel Translation Modes (DS1/J1)
Channels (received time slots)
Time Slots on
system side
Channels (received time slots)
Time Slots on
system side
Channel
Translation
Mode 0
Channel
Translation
Mode 1
Channel
Translation
Mode 0
Channel
Translation
Mode 1
FS/DL
0
unequipped
16
1
131717
2
141818
3
151919
Unequipped
4
unequipped
20
4
5
162121
5
6
172222
6
7
182323
Unequipped
8
unequipped
24
7
9919
unequipped
25
8
101020unequipped
26
9
111121unequipped
27
Unequipped
12
unequipped
28
10
13
22
unequipped
29
11
14
23
unequipped
30
12
15
24
unequipped
31
Table 48
Receive Buffer Operation Modes (T1/J1)
SIC1.RBS(1:0)
Buffer Size
TS Offset Programming
(RC(1:0)) + SYPR = input
Slip Performing
11
Bypass
Disabled, RFM recommended with
CMR2.IRSP = 0
B
No