
PEB 20542
PEF 20542
Register Description (ISR2)
Data Sheet
5-226
2000-09-14
RME
Receive Message End Interrupt
This bit set to
’
1
’
indicates that the reception of one message is
completed, i.e. either
–
one message which fits into RFIFO not exceeding the receive FIFO
threshold, or
–
the last part of a message, all in all exceeding the receive FIFO
threshold
is stored in the RFIFO.
The complete message length can be determined by reading the
RBCL
/
RBCH
registers. The number of bytes stored in RFIFO is given by the 5,
4, 2 or 1 least significant bits of register
RBCL
, depending on the
selected RFIFO threshold (bit field
’
RFTH(1:0)
’
in register
CCR3H
).
Additional frame status information is available in the
RSTA
byte, stored
in the RFIFO as the last byte of each frame.
Note: After the RFIFO contents have been read, an
CMDRH
:RMC
command must be issued to free the RFIFO for new receive data.
(hdlc mode)
TCD
Termination Character Detected Interrupt
This bit is set to
’
1
’
, if a termination character (
TCR
) has been detected
in the receive data stream or an
’
RFRD
’
command, issued in the
CMDRH
register, has been completed. The SCC will insert a
’
block end
’
indication
to the RFIFO. The actual block length can be determined by reading
register
RBCL
.
Note: After the RFIFO contents have been read, an
CMDRH
:RMC
command must be issued to free the RFIFO for new receive data.
(async/bisync mode)
RFS
Receive Frame Start Interrupt
This bit is set to
’
1
’
, if the beginning of a valid frame is detected by the
receiver. A valid frame start is detected either if a valid address field is
recognized (in all operating modes with address recognition) or if a start
flag is recognized (in all operating modes with no address recognition).
(hdlc mode)
TIME
Time Out Interrupt
This bit is set to
’
1
’
, if the time out limit is exceeded, i.e. no new character
was received in a programmable period of time (refer to register
TOLEN
bit fields
’
TOIE
’
and
’
TOLEN
’
for more information).
(async mode)