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Data Sheet
409
Rev. 1.2, 2006-01-26
QuadFALCTM
PEF 22554 E
E1 Registers
RFS3
4
rsc
Receive Frame Start - HDLC Channel 3
This is an early receiver interrupt activated after the start of a valid frame
has been detected, i.e. after an address match (in operation modes
providing address recognition), or after the opening flag (transparent
mode 0) is detected, delayed by two bytes. After an RFS2 interrupt, the
contents of
RAL1
RSIS3 bits 3 to 1
Are valid and can be read by the external micro controller.
0B
no frame start has been detected on HDLC channel 3.
1B
a frame start has been detected on HDLC channel 3, RAL1 and
RSIS3(3:1) are valid.
RDO3
3
rsc
Receive Data Overflow - HDLC Channel 3
This interrupt status indicates that the external micro controller did not
respond fast enough to an RPF3 or RME3 interrupt and that data in
RFIFO3 has been lost. Even when this interrupt status is generated, the
frame continues to be received when space in the RFIFO3 is available
again.
Note: Whereas the bit RSIS3.RDO3 in the frame status byte indicates
whether an overflow occurred when receiving the frame currently
accessed in the RFIFO3, the ISR5.RDO3 interrupt status is
generated as soon as an overflow occurs and does not necessarily
pertain to the frame currently accessed by the processor.
0B
no receive data overflow has been detected on HDLC channel 3.
1B
a receive data overflow has been detected on HDLC channel 3.
ALLS3
2
rsc
All Sent - HDLC Channel 3
This bit is set if the last bit of the current frame has been sent completely
and XFIFO3 is empty. This bit is valid in HDLC mode only.
0B
data transmission is in progress on HDLC channel 3.
1B
data transmission is idle on HDLC channel 3, XFIFO3 is empty.
XDU3
1
rsc
Transmit Data Underrun - HDLC Channel 3
Transmitted frame was terminated with an abort sequence because no
data was available for transmission in XFIFO3 and no XME3 was issued.
Note: Transmitter and XFIFO3 are reset and deactivated if this condition
occurs. They are reactivated not before this interrupt status register
has been read. Thus, XDU3 should not be masked via register
IMR5. Additionally, CMDR4.SRES3 must be set after XDU occurs
to reset the signaling transmitter.
0B
data transmission is in progress on HDLC channel 3.
1B
data transmission has been stopped due to data underrun on
HDLC channel 3.
RPF3
0
rsc
Receive Pool Full - HDLC Channel 3
32 bytes of a frame have arrived in the receive FIFO3. The frame is not
yet completely received.
0B
data reception is in progress on HDLC channel 3.
1B
data has been stored in RFIFO3 and can be read.
Field
Bits
Type
Description