HC4GX15 Datasheet, PDF (507/668 Pages) Altera Corporation – HardCopy IV Device Handbook

Chapter 2: HardCopy IV GX Dynamic Reconfiguration
2–49
The rx_tx_duplex_sel[1:0] Port
Figure 2–17 shows the ALTGX_RECONFIG instance connected to both the ALTGX
instance 1 and ALTGX instance 2.
Figure 2–17. Example of the ALTGX_RECONFIG and ALTGX Instances Set Up for the Offset Cancellation Process of a
Receiver Channel
reconfig_clk
Set the What is the number of
channels controlled by the
reconfig controller? option = 12
reconfig_fromgxb[50:0] (1)
ALTGX_RECONFIG Instance
busy
Set the What is the starting
channel number? option = 0
ALTGX Instance 1
(Number of Channels is 5)
reconfig_fromgxb1[33:0]
Set the What is the starting
channel number? option = 8
ALTGX Instance 2
(Number of Channels is 3)
reconfig_fromgxb2[16:0]
Notes to Figure 2–17:
(1) reconfig_fromgxb[50:0] = {reconfig_fromgxb2[16:0], reconfig_fromgxb1[33:0]}.
(2) All the channels are regular transceiver channels.
ALTGX Instances and ALTGX_RECONFIG Instance Connections
1. Connect the reconfig_fromgxb1[33:0] output port from ALTGX instance 1 to
the reconfig_fromgxb[33:0] input port of the ALTGX_RECONFIG instance.
2. Similarly, connect the reconfig_fromgxb2[16:0] output port from ALTGX
instance 2 to the reconfig_fromgxb[50:17] input port of the
ALTGX_RECONFIG instance.
3. Connect the reconfig_togxb[3:0] output port of the ALTGX_RECONFIG
instance to the reconfig_togxb[3:0] input ports of both ALTGX instance 1
and ALTGX instance 2. For more information, refer to “Connecting the
reconfig_fromgxb and reconfig_togxb Ports” on page 2–40.
Dynamic Reconfiguration Controller-Offset Cancellation Control Sequence
1. The ALTGX_RECONFIG instance automatically performs offset cancellation on all
receiver channels of the ALTGX instances connected to it on power up.
2. The busy signal is low for the first reconfig_clk clock cycle after power up.
3. The busy signal gets asserted for the second reconfig_clk clock cycle after
power up.
4. The de-assertion of the busy signal indicates the successful completion of the
offset cancellation process.
The rx_tx_duplex_sel[1:0] Port
The width of the rx_tx_duplex_sel port is fixed to 2 bits. The
rx_tx_duplex_sel[1:0] port is available for selection in all dynamic
reconfiguration modes.
© June 2009 Altera Corporation
HardCopy IV Device Handbook, Volume 3