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that the user can either use the ARM daughter board in
the ARM board for development, or for programming
the daughter board which can then be used in other
projects.
The ARM board connects to the ARM daughter board
(EB034) via four DIL PCB sockets (10 + 10). These connect
all the ARM device signals to the ARM daughter board,
thus allowing programming and use of all the functions
available on the ARM device.
The ARM board has five I/O ports, in the form of 9-way
D-type connectors. These allow the ARM board to be
fully compatible with the E-blocks range. The first four
D-type connectors (J5-8) connect all 32 general-purpose
I/O from the ARM device. Most of these general-purpose
I/O pins have multiple functions - such features as SPI.
USART communication and analogue to digital
converters. Please see the datasheet of the actual ARM
device that you are using for complete list of functions
(
www.atmel.com
).
The ARM device has four dedicated analogue to digital
converters and four general-purpose I/O with analogue
functionality. Therefore all these either signals have
been grouped together, on the fifth D-type connector
(J9), which can be used as a fully analogue port.
Please note that the four general-purpose I/O are also
available on the another D-type connector (J8) and
care must be taken to ensure that these signals are not
connected to any other device whilst using them on these
fully analogue port (J9).
A full table of I/O connections is provided on page 7.
3. Programming (software)
There are two ways of getting the ARM board into
programming mode:
With the power to the board on press and hold down the
PROG button switch. Then quickly press and release the
RESET button switch. If your drivers are set up then you
will hear Windows give a double tone to indicate a USB
device has been discovered.
If you have used D4 or B5 as an output then you may find
that the driver gets disassociated. In this case you can
use this alternate method:
Turn power to the ARM board off using SW 1. Press and
hold the PROG button switch down. Turn power on with
SW1, and less than half a second after release the PROG
button switch.
4. Reset push button
PB1 provides a reset by pulling the NRST pin low. This
will reset the ARM device thus enabling any program to
restart.
Please note that the NRST can be programmed so that the
reset pin will not function as a reset. See the datasheet
for the ARM device that you are using for more details on
disabling the NRST as a reset.
5. Frequency selection
The clock signal for this board is generated from either an
internal RC clock signal or the on-board external crystal.
The on-board crystal is set to 18.432MHz as this enables
the USB synchronisation speed to be correct - as stated
by the software specification.
The device can also use an internal PLL to set the
frequency for the device. Please see the datasheet of the
device for further information regarding using the PLL.
