Copyright
©
2012
congatec
AG
CEVA_c_m10
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3.2.3
Power-up Control
The Power‑up control switches the ATX power supply on or off. The SUS_S3# activates the ATX power supply by driving the PS_ON# signal.
If DC power input (M2, M7) is used, voltage regulators start after ap12V.
The native system power‑up support of congatec modules uses the
‘SUS_S3#’
signal
to control the
‘PS_ON#’
signal
,
which switches the ATX
power supply on or off
.
When using the
SUS_S3#’
signal, the COM Express™ module is capable of supporting Suspend to RAM (S3).
When the system goes to Suspend to RAM (S3) or Soft Off (S5), the
‘SUS_S3#’
signal is asserted by the chipset of the module. Through the
use of an inverter, the low active
‘PS_ON#’
signal goes high and switches off the ATX power supply. If the system resides in a power‑down
system state, any system wake‑up event invokes the chipset of the module to deassert the
‘SUS_S3#’
signal.
This transitions the system to
Full‑on (S0).
How Suspend to RAM is implemented on a COM Express™ module may differ depending on the module manufacturer. For this reason, it is
recommended that a hardware jumper be implemented on the carrier board in order to provide the ability to choose if the
‘PS_ON#’
signal
should be controlled either by the
‘SUS_S3#’
signal or ‘
SUS_S5#’
signal. This is accomplished on earlier conga‑CEVAL revisions through the
use of jumper X63. The conga-CEVAL revision B.0 and later do not implement the jumper X63 (see note below).
Note
On conga-CEVAL revision B.0 and later, the X63 4-pin jumper connector that switches between SUS_S3# and SUS_S5# is not available
because the PS_ON# is driven only by SUS_S3#.
3.2.4
Module Type Detection
The COM Express™ Specification includes four signals (
‘TYPE0#’
,
‘TYPE1#’,
‘TYPE2#’
and
‘TYPE10#’
) to determine the pinout type of the
module connected to the carrier board. These pins are either left open (NC) or strapped to ground (GND) by the module to encode the pinout
type according to the table below. The
‘TYPE10#’
pin is for dual use. It indicates to the carrier board that a Type 10 module is installed. It also
indicates that a Rev 1.0 or Rev 2.0 module is installed. For more information, refer to the COM Express™ Specification Rev 2.0.
Table 4
Module Type Detection
Module Type
Pin TYPE0#
Pin TYPE1#
Pin TYPE2#
Pin TYPE10#
Module Type 1
X (not present)
X (not present)
X (not present)
NC
Module Type 2
NC
NC
NC
NC
Module Type 3
GND
NC
NC
NC
No IDE interface
Module Type 4
NC
GND
NC
NC
No PCI interface
Module Type 5
GND
GND
NC
NC
No IDE, no PCI interface
Module Type 6
NC
NC
GND
NC
No IDE, no PCI interface
