HC4GX15 Datasheet, PDF (473/668 Pages) Altera Corporation – HardCopy IV Device Handbook

Chapter 2: HardCopy IV GX Dynamic Reconfiguration
2–15
Quartus II MegaWizard Plug-In Manager Interfaces to Support Dynamic Reconfiguration
Table 2–2. Dynamic Reconfiguration Controller Port List (ALTGX_RECONFIG Instance) (Part 5 of 9)
Port Name
tx_preemp_0t[4..0] (1)
tx_preemp_1t[4..0] (1)
Input/
Output
Input
Input
Description
This is an optional pre-emphasis control for pre-tap for the transmit
buffer. Depending on what value you set at this input, the controller
dynamically writes the value to the pre-emphasis control register of
the transmit buffer. This signal controls both pre-emphasis positive
and its inversion.
The width of this signal is fixed to 5 bits if you enable either the Use
'logical_channel_address' port for Analog controls
reconfiguration option or the Use same control signal for all the
channels option in the Analog controls screen. Otherwise, the
width of this signal is 5 bits per channel.
For more information, refer to “Dynamically Reconfiguring PMA
Controls” on page 2–53.
The following values are the legal settings allowed for this signal:
0 represents 0
1-15 represents -15 to -1
16 represents 0
17 - 31 represents 1 to 15
In PCI Express (PIPE) configuration, set tx_preemp_0t[4:0]
to 5'b00000 when you do a rate switch from Gen 1 to Gen 2 mode.
This is to ensure that tx_preemp_0t[4:0] does not add to the
signal boost, when tx_pipemargin, tx_pipeswing, and
tx_pipedeemph take affect in PCI Express (Gen 2) mode.
For more information, refer to the Programmable Pre-Emphasis
section of the HardCopy IV GX Transceiver Architecture chapter in
volume 3 of the HardCopy IV Device Handbook.
This is an optional pre-emphasis write control for the first post-tap
for the transmit buffer. Depending on what value you set at this
input, the controller dynamically writes the value to the first
post-tap control register of the transmit buffer.
The width of this signal is fixed to 5 bits if you enable either the Use
'logical_channel_address' port for Analog controls
reconfiguration option or the Use same control signal for all the
channels option in the Analog controls screen. Otherwise, the
width of this signal is 5 bits per channel.
For more information, refer to “Dynamically Reconfiguring PMA
Controls” on page 2–53 for additional details and the
Programmable Pre-Emphasis section of the HardCopy IV GX
Transceiver Architecture chapter in volume 3 of the HardCopy IV
Device Handbook.
© June 2009 Altera Corporation
HardCopy IV Device Handbook, Volume 3