IPSERIALLITE Altera, IPSERIALLITE Datasheet - Page 80

• Manufacturer Part Number: IPSERIALLITE
• Manufacturer: Altera

Specifications of IPSERIALLITE

• Lead Free Status / RoHS Status: Not Compliant

SerialLite Link Configuration
3–48
SerialLite MegaCore Function User Guide
Figure 3–29. FIFO Buffer Structure (Flow Control Enabled With Backup Pause)
FIFO Buffer Thresholds
When flow control is enabled, a threshold is established for triggering
flow control. You control the size of this threshold. The Parameterize -
SerialLite MegaCore function wizard establishes a default that works, but
you can create a larger threshold if you desire. The benefit of a larger
threshold is that flow control occurs less often. The cost is the fact that
more memory resources are required, and meeting performance could be
more of a challenge.
If a backup pause is used, a second threshold is created (see
This threshold is automatically set by the wizard, and cannot be changed.
There is no reason to change it, and for that reason it is considered part of
the headroom above the main threshold. The only threshold you need to
control is the primary threshold that initiates flow control.
FIFO Buffer Headroom
When flow control is enabled, the SerialLite MegaCore logic monitors the
triggering receive FIFO buffer, and when a threshold is reached, issues a
PAUSE instruction. It takes some time for the PAUSE instruction to be
issued, traverse the connection, and for transmission to be stopped. It
takes more time for all data that has already been transmitted to be stored
in the receive FIFO buffer.
Backup Threshold
Control Threshold
Primary Flow
MegaCore Function Version 1.1.0
Width set automatically
Threshold
SerialLite wizard
SerialLite wizard
Depth set in
Depth set in
Altera Corporation
Figure
August 2005
3–29).