peb2256 Infineon Technologies Corporation, peb2256 Datasheet - Page 289

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

9.4
Receive FIFO - HDLC Channel 1 (Read)
RFIFO
RFIFO
Reading data from RFIFO of HDLC channel 1 can be done in an 8-bit (byte) or 16-bit
(word) access depending on the selected bus interface mode. The LSB is received first
from the serial interface.
The size of the accessible part of RFIFO is determined by programming the bits
CCR1.RFT(1:0) (RFIFO threshold level). It can be reduced from 32 bytes (reset value)
down to 2 bytes (four values: 32, 16, 4, 2 bytes).
Data Transfer
Up to 32 bytes/16 words of received data can be read from the RFIFO following an RPF
or an RME interrupt.
RPF Interrupt: A fixed number of bytes/words to be read (32, 16, 4, 2 bytes). The
message is not yet complete.
RME Interrupt: The message is completely received. The number of valid bytes is
determined by reading the RBCL, RBCH registers.
RFIFO is released by issuing the RMC (Receive Message Complete) command.
Receive Buffer Delay (Read)
RBD
RBD(5:0)
Data Sheet
RF15
RF7
Detailed Description of E1 Status Registers
7
7
Receive Elastic Buffer Delay
These bits informs the user about the current delay (in time slots)
through the receive elastic buffer. The delay is updated every 512 or
256 bits (SIC1.RBS(1:0)). Before reading this register the user has to
set bit DEC.DRBD in order to halt the current value of this register.
After reading RBD updating of this register is enabled. Not valid if the
receive buffer is bypassed.
000000 = Delay < 1 time slot
...
111111 = Delay > 63 time slots
RBD5
RBD4
289
RBD3
RBD2
RBD1
RBD0
FALC56 V1.2
RF0
RF8
E1 Registers
0
0
PEB 2256
2002-08-27
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