Vitesse Disparity Example - Xilinx RocketIO X User Manual

R

Vitesse Disparity Example

To support other protocols, the transceiver can affect the disparity mode of the serial data
transmitted. For example, Vitesse channel-to-channel alignment protocol sends out:
or
Instead of:
or
The logic must assert TXCHARDISPVAL to cause the serial data to send out two negative
running disparity characters.
Transmitting Vitesse Channel Bonding Sequence
The RocketIO X core receives this data but must have the CHAN_BOND_SEQ set with the
disp_err
transmission.
Receiving Vitesse Channel Bonding Sequence
On the RX side, the definition of the channel bonding sequence uses the
specify the flipped disparity.
52
K28.5+ K28.5+ K28.5- K28.5-
K28.5- K28.5- K28.5+ K28.5+
K28.5+ K28.5- K28.5+ K28.5-
K28.5- K28.5+ K28.5- K28.5+
TXBYPASS8B10B
| TXCHARISK
| | TXCHARDISPMODE
| | | TXCHARDISPVAL
| | | | TXDATA
| | | | |
0 1 0 0 10111100
0 1 0 1 10111100
0 1 0 0 10111100
0 1 0 1 10111100
bit set High for the cases when TXCHARDISPVAL is set High during data
10-bit literal value
| disp_err
| | char_is_k
| | | 8-bit_byte_value
| | | |
CHAN_BOND_SEQ_1_1 = 0 0 1 10111100
CHAN_BOND_SEQ_1_2 = 0 1 1 10111100
CHAN_BOND_SEQ_1_3 = 0 0 1 10111100
CHAN_BOND_SEQ_1_4 = 0 1 1 10111100
CHAN_BOND_SEQ_LEN = 4
CHAN_BOND_SEQ_2_USE = FALSE
www.xilinx.com
1-800-255-7778
Chapter 2: Digital Design Considerations
K28.5+ (or K28.5-)
K28.5+ (or K28.5-)
K28.5- (or K28.5+)
K28.5- (or K28.5+)
matches K28.5+ (or K28.5-)
matches K28.5+ (or K28.5-)
matches K28.5- (or K28.5+)
matches K28.5- (or K28.5+)
RocketIO™ X Transceiver User Guide
UG035 (v1.5) November 22, 2004
disp_err bit to