DS3181/DS3182/DS3183/DS3184
363
12.14.4.1 Register Bit Descriptions
Register Name:
PP.RCR
Register Description:
Packet Processor Receive Control Register
Register Address:
(1,3,5,7)C0h
Bit #
15
14
13
12
11
10
9
8
Name
RMNS7
RMNS6
RMNS5
RMNS4
RMNS3
RMNS2
RMNS1
RMNS0
Default
0
Bit #
7
6
5
4
3
2
1
0
Name
Reserved
RFPD
RF16
RFED
RDD
RBRE
RPTE
Default
0
Bits 15 to 8: Receive Minimum Packet Size (RMNS[7:0]) – These eight bits indicate the minimum allowable
packet size in bytes. The size includes the FCS bytes, but excludes bit/byte stuffing. Note: In FCS-32 mode,
packets with six bytes are the minimum packet size allowed, in FCS-16 mode, packets with four bytes are the
minimum packet size allowed, and when FCS processing is disabled, packets with two bytes are the minimum
packet size allowed. Packets less than the minimum size will be aborted.
Bit 5: Receive FCS Processing Disable (RFPD) – When 0, FCS processing is performed (the packets have an
FCS appended). When 1, FCS processing is disabled (the packets do not have an FCS appended).
Bit 4: Receive FCS-16 Enable (RF16) – When 0, the error checking circuit uses a 32-bit FCS. When 1, the error
checking circuit uses a 16-bit FCS. This bit is ignored when FCS processing is disabled.
Bit 3: Receive FCS Extraction Disable (RFED) – When 0, the FCS bytes are discarded. When 1, the FCS bytes
are passed on. This bit is ignored when FCS processing is disabled.
Bit 2: Receive Descrambling Disable (RDD) – When 0, descrambling is performed. When 1, descrambling is
disabled.
Bit 1: Receive Bit Reordering Enable (RBRE) – When 0, bit reordering is disabled (The first bit received is stored
in the MSB of the receive FIFO byte). When 1, bit reordering is enabled (The first bit received is stored in the LSB
of the receive FIFO byte).
Bit 0: Receive Pass-Through Enable (RPTE) – When 0, pass-through mode is disabled and packet processing is
enabled. When 1, pass-through mode is enabled, and all packet-processing functions except descrambling and bit
reordering are disabled.
Register Name:
PP.RMPSC
Register Description:
Packet Processor Receive Maximum Packet Size Control Register
Register Address:
(1,3,5,7)C2h
Bit #
15
14
13
12
11
10
9
8
Name
RMX15
RMX14
RMX13
RMX12
RMX11
RMX10
RMX9
RMX8
Default
0
1
0
Bit #
7
6
5
4
3
2
1
0
Name
RMX7
RMX6
RMX5
RMX4
RMX3
RMX2
RMX1
RMX0
Default
0
Bits 15 to 0: Receive Maximum Packet Size (RMX[15:0]) – These 16 bits indicate the maximum allowable
packet size in bytes. The size includes the FCS bytes, but excludes bit/byte stuffing. Note: If the maximum packet
length is less than the minimum packet length, all packets will be aborted. When packet processing is disabled,
these 16 bits indicate the "packet" size the incoming data is to be broken into.