Spartan-3E FPGA Industrial Micromodule
User Manual
Signal
FPGA pin
FPGA ball
PB
IP
(bank 2)
V16
Table 6: user button signal details.
The input is normally low. The input is
pulled up when pressed.
Configuration Switches
The micromodule hosts 4 DIP switches on
the top side: S1; S2, S3 and S4.
For customers requesting a sufficient
amount of units, the micromodules can be
manufactured replacing the switches by
fixed connections.
DIP Switch S1
S1 enables / disables the communication
between the Cypress EZ-USB FX2 micro-
controller and the I2C CMOS Serial EEP-
ROM.
Turn S1 off when programming the USB
EEPROM (storing the USB vendor ID and
device ID). This will force the USB micro-
controller to provide its default vendor ID
and device ID.
S1
position
EEPROM (on)*
EEPROM enabled
Off (off)
EEPROM disabled
Table 7: S1 (* default: EEPROM).
For further information, please read para-
graph “Software Configuration”.
DIP Switch S2
S2 enables / disables the reset line. The
reset line (available also on 2 contacts of
the B2B connector) resets the USB micro-
controller and the FPGA.
S2 has to be turned off (
Reset
) if the user
wants to program the SPI Flash memory in
direct mode. For programming the SPI
Flash memory in indirect mode over JTAG,
S2 has to be turned on (
Run
).
S2
position
Run (on)*
system running
Reset (off)
system reset
Table 8: S2 (*default:
Run
).
For further information, please read para-
graph “Software Configuration”.
DIP Switch S3
S3 conditionally / unconditionally enables
the 1.2 V and 2.5 V power rails.
When S3 is turned on, the 1.2 V and 2.5 V
power rails are controlled by the USB mi-
crocontroller. At start-up, the USB micro-
controller switches off the 1.2 V and 2.5 V
power rails and starts up the module in
low-power mode. After enumeration, the
USB microcontroller firmware switches the
1.2 V and 2.5 V power rails on, if enough
current is available from the USB bus.
When S3 is turned off, the 1.2 V and 2.5 V
power rails are always enabled.
S3
position
FX2 PON (on)*
rails controlled by FX2
PON (off)
rails always enabled
Table 9: S3 (* default: FX2 PON).
Warning!
When S3 is turned on (
FX2
PON
), make sure that no signals are ap-
plied to the input pins when power-rails
are disabled by the USB microcontroller.
The 3.3 V power-rail though is out of the
control of the USB-microcontroller and is
supplied down-converting the 5 V power
supply provided by either the USB-bus or
the B2B receptacle connector. In this case,
signals that are applied to the 3.3 V I/O
Trenz Electronic GmbH
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