Link¶

A link represents the physical connection between a TX and RX and can be used to modify the TX/RX parameters, run 2D statistical eye scans and access other metrics for judging the quality of the link.

Create links¶

Links can be created using RX and TX. To create a link, use the factory function create_links(). Here’s an example of creating a link

"""
Other imports
"""
from chipscopy.api.ibert import create_links

"""
Boilerplate stuff - Create a session, get the IBERT core etc etc
"""

quad_204 = one(ibert.gt_groups.filter_by(name="Quad_204"))

ch_0 = one(quad_204.gts.filter_by(name="CH_0"))
ch_1 = one(quad_204.gts.filter_by(name="CH_1"))
ch_2 = one(quad_204.gts.filter_by(name="CH_2"))
ch_3 = one(quad_204.gts.filter_by(name="CH_3"))

# Create single link
link_0 = one(create_links(rxs=ch_0.rx, txs=ch_0.tx))

# Create multiple links in one shot
remaining_3_links = create_links(rxs=[ch_1.rx, ch_2.rx, ch_3.rx], txs=[ch_1.tx, ch_2.tx, ch_3.tx])

Note

When creating multiple links in one shot, please ensure that the length of the RX and TX lists are equal.

Since cs_server doesn’t support all Xilinx GTs architectures OR non-Xilinx GTs, a link can be created with an “Unknown” TX/RX.

Note

Unknown TX/RX refers to TX/RXs that aren’t supported by cs_server.

To do this, instead of TX/RX object, pass in an empty str i.e. "". Example

# Create link with unknown TX
link_0 = one(create_links(rxs=ch_0.rx, txs=""))

# Create multiple links
remaining_3_links = create_links(rxs=["", ch_2.rx, ch_3.rx], txs=[ch_1.tx, ch_2.tx, ""])

In the above snippet, link_0.tx = None. Similarly, remaining_3_links[0].rx = None and remaining_3_links[2].tx = None.

Attributes of Link object¶

The attributes of the Link class instance are listed here and are accessible via the python . operator i.e. <link_obj>.<attribute>.

Link attributes¶
Attribute	Description
`name`	Name of the link
`handle`	Handle of the link
`rx`	`RX` instance attached to the link
`tx`	`TX` instance attached to the link
`link_group`	Link group the link is in
`eye_scan`	Eye scan object attached to the `rx`
`ber`	Bit Error Rate
`status`	Status of the link. If link is not locked, this is equal to `"No Link"`
`line_rate`	Line rate with units
`bit_count`	#bits received
`error_count`	#errors received

Generate report¶

To generate a link report, call the generate_report() method. This will print the report in a tabular form to stdout.

Example

link_0.generate_report()

To get a string representation of the report, you can pass a callable to the function.

Get all links¶

To get all the links, use the function get_all_links().

Delete link¶

To delete a link, use the factory function delete_links().

"""
Other imports
"""
from chipscopy.api.ibert import delete_links, get_all_links

"""
Boilerplate stuff - Create a session, get the IBERT core etc etc
"""

# Assume 'link_0' is a Link object & 'remaining_3_links' is a list of Link's
.
.
.
# Delete one link
delete_links(link_0)

len(get_all_links())
>>> 3

# Delete 3 links
delete_links(remaining_3_links)

len(get_all_links())
>>> 0

Warning

Once the link is deleted, any references to the deleted link instance will be stale and are not safe to use.