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DS3171/DS3172/DS3173/DS3174
162
Register Name:
HDLC.RSR
Register Description:
HDLC Receive Status Register
Register Address:
(0,2,4,6)B4h
Bit
# 15 14 13 12 11 10 9 8
Name
-- -- -- -- -- -- -- --
Bit
# 7 6 5 4 3 2 1 0
Name
-- -- -- -- --
RFF RFE RHDA
Bit 2: Receive FIFO Full (RFF)
– When 0, the Receive FIFO contains 255 or less bytes of data. When 1, the
Receive FIFO is full.
Bit 1: Receive FIFO Empty (RFE)
– When 0, the Receive FIFO contains at least one byte of data. When 1, the
Receive FIFO is empty.
Bit 0: Receive HDLC Data Available (RHDA)
– When 0, the Receive FIFO contains less data than the Receive
HDLC data available level (RDAL[4:0]). When 1, the Receive FIFO contains the same or more data than the
Receive HDLC data available level.
Register Name:
HDLC.RSRL
Register Description:
HDLC Receive Status Register Latched
Register Address:
(0,2,4,6)B6h
Bit
# 15 14 13 12 11 10 9 8
Name
-- -- -- -- -- -- -- --
Bit
# 7 6 5 4 3 2 1 0
Name RFOL -- --
RPEL RPSL RFFL -- RHDAL
Bit 7: Receive FIFO Overflow Latched (RFOL)
– This bit is set when a Receive FIFO overflow condition occurs.
An overflow condition results in a loss of data.
Bit 4: Receive Packet End Latched (RPEL)
– This bit is set when an end of packet is stored in the Receive FIFO.
Bit 3: Receive Packet Start Latched (RPSL)
– This bit is set when a start of packet is stored in the Receive FIFO.
Bit 2: Receive FIFO Full Latched (RFFL)
– This bit is set when the RFF bit transitions from 0 to 1.
Bit 0: Receive HDLC Data Available Latched (RHDAL)
– This bit is set when the RHDA bit transitions from 0 to
1.