Semiconductor Group
276
09.98
PEB 22554
Operational Description T1 / J1
Continuous reception:
CCR1.BRM = 1
Interrupts are generated every 32 (16, 4, 2) bytes. After detecting an HDLC flag, byte
sampling is stopped, the receive status byte is stored in RFIFO and an RME interrupt is
generated.
Receiption with enabled BOM filter:
CCR2.RBFE = 1
The BOM-receiver will only accept BOM frames after detecting 7 out of 10 equal BOM
pattern. The BOM pattern is stored in the RFIFO adding a receive status byte, marking
a BOM frame (RSIS.HFR) and generating an interrupt status ISR0.RME. The current
state of the BOM receiver is indicated in register SIS.IVB. When the valid BOM pattern
disappears an interrupt ISR0.BIV is generated.
The user may switch between these modes at any time. Byte sampling may be stopped
by deactivating the BOM receiver (MODE.BRAC). In this case the receive status byte is
added, an interrupt is generated and HDLC-mode is entered. Whether the QuadFALC
operates in HDLC or BOM mode may be checked by reading the Signaling Status
Register (SIS.BOM).
8.1.5
The QuadFALC supports the DL-channel protocol using the F72 (SLC96) format as
follows:
Sampling of DL bits is done on a multiframe basis and stored in the registers RDL1-3.
A receive multiframe begin interrupt is provided to read the received data DL bits. The
contents of registers XDL1-3 is subsequently sent out on the transmit multiframe basis
if it is enabled via FMR1.EDL. A transmit multiframe begin interrupt requests for
writing new information to the DL-bit registers.
If enabled via CCR1.EDLX/EITS=10 , the DL bit information from frame 26 to 72 is
stored in the Receive FIFO of the signaling controller.The DL bits stored in the XFIFO
are inserted in the outgoing datastream. If CCR1.EDLX is cleared, a HDLC- or a
transparent- frame could be sent or received via the RFIFO / XFIFO.
4 Kbit/s Data Link Access in F72 Format