peb2256 Infineon Technologies Corporation, peb2256 Datasheet - Page 223

• Manufacturer Part Number: peb2256
• Description: E1/t1/j1 Framer And Line Interface Component For Long And Short Haul Applications
• Manufacturer: Infineon Technologies Corporation

RFT(1:0)
Data Sheet
RFIFO Threshold Level - HDLC Channel 1
The size of the accessible part of RFIFO can be determined by
programming these bits. The number of valid bytes after a RPF
interrupt is given in the following table:
RFT1
0
0
1
1
The value of RFT1, 0 can be changed dynamically.
– If reception is not running or
– after the current data block has been read, but before the
command CMDR.RMC is issued (interrupt controlled data transfer).
Note: It is seen that changing the value of RFT1, 0 is possible even
RFT1
0
0
1
1
during the reception of one frame. The total length of the
received frame can be always read directly in RBCL, RBCH
after a RPF interrupt, except when the threshold is increased
during reception of that frame. The real length can then be
inferred by noting which bit positions in RBCL are reset by a
RMC command (see table below):
RFT0
0
1
0
1
RFT0
0
1
0
1
223
Size of Accessible Part of RFIFO
32 bytes (reset value)
16 bytes
4 bytes
2 bytes
Bit Positions in RBCL Reset by a
CMDR.RMC Command
RBC(4:0)
RBC(3:0)
RBC(1:0)
RBC0
FALC56 V1.2
E1 Registers
PEB 2256
2002-08-27