Achronix Speedster22i 10G/40G/100G Ethernet - Manual (Page 90)

90 UG029, September 6, 2013
9
Parallel
Detection Fault
Error with parallel detection. When the remote device does
not support autonegotiation the autonegotiation module
function falls back to parallel detection only monitoring the
sync indications from the PCS layers. If none or more than
one sync is detected the error is asserted.
RO
LH
15:10 Reserved Bits always set to ‘0’. RO
Ability Register Bits (KXAN_ABILITY / KXAN_REM_ABILITY)
During auto-negotiation, a 48-bit ability word is exchanged between the local and the remote
device. Note that the ability word is split into three registers within the register map of the
module (ABILITY_0/1/2).
Table 51 – KXAN_ABILITY_0 / KXAN_REM_ABILITY_0 Register Description
Bit(s) Name Description
Reset
value
4:0 S (Selector)
The selector field is a constant value defining 802.3ap
support. The suggested value is 0x01.
0x1
9:5
E (Echoed
nonce)
Echoed Nonce field contains the nonce received from
the link partner. When Acknowledge is set to logical
zero, the bits in this field shall contain logical zeros.
When Acknowledge is set to logical one, the bits in this
field shall contain the value received in the Transmitted
Nonce field from the link partner.
0x0
12:10
C (Pause
ability)
C2 (bit-12) is reserved
a) The C0 bit (bit-10) is the PAUSE bit indicating that the
device is capable of providing the symmetric PAUSE
functions.
b) The C1 bit (bit-11) indicates that asymmetric PAUSE
is supported. The value of the PAUSE bit (C0) when the
C1 is set indicates the direction the PAUSE frames are
supported for flow across the link.
0x0
13 Remote Fault
The Remote Fault bit provides a standard transport
mechanism for the transmission of simple fault
information.
0x0
14 Acknowledge
Acknowledge (Ack) is used by the auto-negotiation
function to indicate that a device has successfully
received its link partner’s Link Codeword.
0x0
15 Next Page
If the device does not have any Next Pages to send, the
NP bit shall be set to logical zero. If a device wishes to
engage in Next Page exchange, it shall set the NP bit to
logical one.
0x0
Table 52 – KXAN_ABILITY_1 / KXAN_REM_ABILITY_1 Register Description
Bit(s) Name Description
Reset
value
4:0
T (Transmitted
nonce)
Transmitted Nonce field contains a random or
pseudo-random number. A new value shall be
generated for each entry to the Ability Detect state.
0x1f
15:5
Technology
Ability
(A10:A0)
Technology Ability field first 11 bits (A10:A0)
Contains information indicating supported
technologies specific to the selector field value when
used with the auto-negotiation for Backplane
0x0