Specifications

CM-X300 CoM
40 CM-X300 Reference Guide Rev 1.31 30-Dec-2010
Table 41 System Signals
CM-X300 Signal
Name
Type
Description
WP1#
I
Hardware write protect for the the entire onboard Data Flash. Prevents all
program/erase operations.
Pulled up to 3.3V internally. Connect to GND to write-protect.
RST-IN#
I/OD
Reset input to CPU and power-on reset output. Pulled up to 3.3V
EXTWAKE#
I
Processor‘s wakeup signal. Pulled down to GND. Pull to 3.3V to generate
wakeup event.
ONKEY#
I
Connects to ON/OFF button. Pull to GND to switch the Power
Management IC ON or OFF. Tying this line to GND for 5 s or more
generates a hard reset.
IRQ
I
Processor‘s interrupt request. Connects to the pin GPIO19.
BOOTENA#
I
May be used to disable internal Data Flash. Normally pulled to GND. Pull
to 3.3V to disable.
RST-OUT#
OD
Active low output, indicated reset state of the CPU‘s Services Power
Management Unit
SYS_EN
O
System Enable for System Peripheral Power Supply. This output, when
deactivated, signals that the system is entering S3/D4/C4 mode
EXT_TBAT
I
Should be connected to the battery‘s internal NTC resistor to make its
temperature measurement by the charger function possible.
3.3.17 I
2
C Bus
Table 42 I
2
C Signals
CM-X300 Signal
Name
Type
Description
I2C-CLK
O
I
2
C bus clock
I2C-DATA
I/O
I
2
C bus bidirectional data
3.3.18 Synchronous Serial Port (SSP)
The CM-X300 features two synchronous serial ports (SSP). These are the PXA3xx ports
SSP1 and SSP3. PXA3xx port SSP1 is available as an alternate function on pins
GPIO[85:88]. Port SSP3 is routed to CAMI connector B.
Table 43 SSP1 Port Signals
CM-X300 Signal
Name
Type
Description
SSPSCLK
I/O
Synchronous Serial Protocol Serial Clock. Shared with pin GPIO85.
Controls the timing of a serial transfer. SSPSCLK can be generated
internally (master mode) or taken from an external source (slave mode)
SSPSFRM
I/O
Synchronous Serial Protocol Serial Frame Indicator. Shared with pin
GPIO86. Indicates the beginning and the end of a serialized data sample.
The SSPSFRM can be generated internally (master mode) or taken from an
external source (slave mode).
SSPTXD
O
Synchronous Serial Protocol Transmit Data. Shared with pin GPIO87.
Serial data out.
SSPRXD
I
Synchronous Serial Protocol Receive Data. Shared with pin GPIO88.
Serial data in.
Table 44 SSP3 Port Signals
CM-X300 Signal
Name
Type
Description
SSPSCLK3
I/O
Synchronous Serial Protocol Serial Clock. Controls the timing of a serial
transfer. SSPSCLK can be generated internally (master mode) or taken
from an external source (slave mode)
SSPSFRM3
I/O
Synchronous Serial Protocol Serial Frame Indicator. Indicates the
beginning and the end of a serialized data sample. The SSPSFRM can be
generated internally (master mode) or taken from an external source (slave
mode).