HC1S25 Datasheet, PDF (14/110 Pages) Altera Corporation – HardCopy Stratix Device Family

Hot Socketing
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■ In instant on mode, the HardCopy Stratix device is available for use
shortly after the device receives power. The on-chip POR circuit
resets all registers. The CONF_DONE output is tri-stated once the POR
has elapsed. No configuration device or configuration data is
necessary.
■ In instant on after 50 ms mode, the HardCopy Stratix device
performs in a fashion similar to the instant on mode, except that there
is an additional delay of 50 ms, during which time the device is held
in reset stage. The CONF_DONE output is pulled low during this time,
and then tri-stated after the 50 ms have elapsed. No configuration
device or configuration data is necessary for this option.
■ In configuration emulation mode, the HardCopy series device
emulates the behavior of an APEX or Stratix FPGA during its
configuration phase. When this mode is used, the HardCopy device
uses a configuration emulation circuit to receive configuration bit
streams. When all the configuration data is received, the HardCopy
series device transitions into an initialization phase and releases the
CONF_DONE pin to be pulled high. Pulling the CONF_DONE pin high
signals that the HardCopy series device is ready for normal
operation. If the optional open-drain INIT_DONE output is used, the
normal operation is delayed until this signal is released by the
HardCopy series device.
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HardCopy II and some HardCopy Stratix devices do not
support configuration emulation mode.
Instant on and instant on after 50 ms modes are the recommended
power-up modes because these modes are similar to an ASIC’s
functionality upon power-up. No changes to the existing board design or
the configuration software are required.
All three modes provide significant benefits to system designers. They
enable seamless migration of the design from the FPGA device to the
HardCopy device with no changes to the existing board design or the
configuration software. The pull-up resistors on nCONFIG, nSTATUS, and
CONF_DONE should be left on the printed circuit board.
For more information, refer to the HardCopy Series Configuration
Emulation chapter in the HardCopy Series Handbook.
Hot Socketing
HardCopy Stratix devices support hot socketing without any external
components. In a hot socketing situation, a device’s output buffers are
turned off during system power up or power down. To simplify board
design, HardCopy Stratix devices support any power-up or power-down
sequence (V_CCIO and V_CCINT). For mixed-voltage environments, you can
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Altera Corporation
September 2008