EP4CE30F29C7N Datasheet, PDF (434/488 Pages) Altera Corporation – Cyclone IV Device Handbook, Volume 1

3–36
Chapter 3: Cyclone IV Dynamic Reconfiguration
Error Indication During Dynamic Reconfiguration
If you are reconfiguring the multipurpose PLL with a different M counter value,
follow these steps:
1. During transceiver PLL reconfiguration, assert tx_digitalreset,
rx_digitalreset, and rx_analogreset signals.
2. Perform PLL reconfiguration to update the multipurpose PLL with the PLL .mif
files.
3. Perform channel reconfiguration and update the transceiver with the GXB
reconfiguration .mif files. If you have multiple channel instantiations connected to
the same multipurpose PLL, reconfigure each channel.
4. Deassert tx_digitalreset and rx_analogreset signals.
5. After the rx_freqlocked signal goes high, wait for at least 4 µs, and then deassert
the rx_digitalreset signal.
Error Indication During Dynamic Reconfiguration
The ALTGX_RECONFIG MegaWizard Plug-In Manager provides an error status
signal when you select the Enable illegal mode checking option or the Enable self
recovery option in the Error checks/data rate switch screen. The conditions under
which the error signal is asserted are:
■ Enable illegal mode checking option—when you select this option, the dynamic
reconfiguration controller checks whether an attempted operation falls under one
of the conditions listed below. The dynamic reconfiguration controller detects
these conditions within two reconfig_clk cycles, deasserts the busy signal, and
asserts the error signal for two reconfig_clk cycles.
■ PMA controls, read operation—none of the output ports (rx_eqctrl_out,
rx_eqdcgain_out, tx_vodctrl_out, and tx_preemp_out) are selected in the
ALTGX_RECONFIG instance and the read signal is asserted.
■ PMA controls, write operation—none of the input ports (rx_eqctrl,
rx_eqdcgain, tx_vodctrl, and tx_preemp) are selected in the
ALTGX_RECONFIG instance and the write_all signal is asserted.
■ Channel reconfiguration and PMA reconfiguration mode select - read operation
option:
■ The reconfig_mode_sel input port is set to 3’b001 (Channel reconfiguration
mode)
■ The read signal is asserted
■ Enable self recovery option—when you select this option, the
ALTGX_RECONFIG MegaWizard Plug-In Manager provides the error output
port. The dynamic reconfiguration controller quits an operation if it did not
complete within the expected number of clock cycles. After recovering from the
illegal operation, the dynamic reconfiguration controller deasserts the busy signal
and asserts the error output port for two reconfig_clk cycles.
1 The error signal is not asserted when an illegal value is written to any of the PMA
controls.
Cyclone IV Device Handbook,
Volume 2
November 2011 Altera Corporation