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Lucent Technologies Inc.
Preliminary Data Sheet, Rev. 1
ORCA Series 3 FPGAs
September 1998
Pin Information
Pin Descriptions
This section describes the pins found on the Series 3 FPGAs. Any pin not described in this table is a user-program-
mable I/O. During configuration, the user-programmable I/Os are 3-stated with an internal pull-up resistor enabled.
If any pin is not used (or not bonded to a package pin), it is also 3-stated with an internal pull-up resistor enabled
after configuration.
Table 68. Pin Descriptions
Symbol
I/O
Description
Dedicated Pins
VDD
—
Positive power supply.
GND
—
Ground supply.
VDD5
—
5 V tolerant select. VDD5 pin locations are shown for package compatibility with
OR2TxxA devices. Connections to 5 V power sources are not used for 5 V tolerant
I/Os in the OR3Txxx devices.
RESET
I
During configuration, RESET forces the restart of configuration and a pull-up is
enabled. After configuration, RESET can be used as a general FPGA input or as a
direct input, which causes all PLC latches/FFs to be asynchronously set/reset.
CCLK
I
In the master and asynchronous peripheral modes, CCLK is an output which
strobes configuration data in. In the slave or synchronous peripheral mode, CCLK
is input synchronous with the data on DIN or D[7:0]. In microprocessor mode, CCLK
is used internally and output for daisy-chain operation.
DONE
I
O
As an input, a low level on DONE delays FPGA start-up after configuration (see
Note).
As an active-high, open-drain output, a high level on this signal indicates that config-
uration is complete. DONE has an optional pull-up resistor.
PRGM
I
PRGM
is an active-low input that forces the restart of configuration and resets the
boundary-scan circuitry. This pin always has an active pull-up.
RD_CFG
I
This pin must be held high during device initialization until the INIT pin goes high.
This pin always has an active pull-up.
During configuration, RD_CFG is an active-low input that activates the TS_ALL func-
tion and 3-states all of the I/O.
After configuration, RD_CFG can be selected (via a bit stream option) to activate the
TS_ALL function as described above, or, if readback is enabled via a bit stream
option, a high-to-low transition on RD_CFG will initiate readback of the configuration
data, including PFU output states, starting with frame address 0.
RD_DATA/TDO
O
RD_DATA/TDO is a dual-function pin. If used for readback, RD_DATA provides
configuration data out. If used in boundary scan, TDO is test data out.
Special-Purpose Pins
M0, M1, M2
I
I/O
During powerup and initialization, M0—M2 are used to select the configuration
mode with their values latched on the rising edge of INIT; see Table 33 for the config-
uration modes. During configuration, a pull-up is enabled.
After configuration, these pins are user-programmable I/O (see Note).
Note: The FPGA States of Operation section contains more information on how to control these signals during start-up. The timing of DONE
release is controlled by one set of bit stream options, and the timing of the simultaneous release of all other configuration pins (and the
activation of all user I/Os) is controlled by a second set of options.