Atmel AT91EB40A, User Manual

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AT91EB40A Evaluation Board User Guide 5-1
Rev. 2635C–ATARM–13-May-05
Section 5
Appendix A – Configuration Straps
5.1 Configuration
Straps
By using the I/O and EBI expansion connectors, users can connect their own peripher-
als to the evaluation board. These peripherals may require more I/O lines than available
while the board is in its default state. Extra I/O lines can be made available by disabling
some of the on-board peripherals or features. This is done using the configuration straps
detailed below. Some of these straps present a default wire (notified by the default men-
tion) that must be cut before soldering the strap.
CB1 On-board CS4 Signal
Closed
(1)
AT91 CS4 signal is connected to the EBI expansion connector
(P1-B21).
Open AT91 CS4 signal is not connected to the EBI expansion connector (P1-B21).
This authorizes users to connect the EBI expansion connector of this board
to the MPI expansion connector of an AT91EB63 Evaluation Board without
conflict problems.
CB2
(2)
Core Power Supply Selection
1 - 2 The AT91 core is powered by 3.3V power supply. NOT ALLOWED for the
AT91R40008.
2 - 3 The AT91 core is powered by 1.8V power supply.
CB3 On-board Boot Chip Select
Closed
(1)
AT91 NCS0 select signal is connected to the Flash memory (U1A or U1B).
See also CB11.
Open AT91 NCS0 select signal is not connected to the Flash memory. This
authorizes users to connect the corresponding chip select signal to their own
resources via the EBI Expansion Connector.