Hardware implementation
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Micro SD socket
A MicroSD memory socket is provided on the PROTEUS module. The US15W SCH contains three
SDIO/MMC ports. SDIO Port 1 is connected to a 4-bit MicroSD card socket. Port 2 is connected to a
ZIF connector and port 0 is not used.
The SDIO/MMC controller supports MMC4.0 and SDIO1.1 specifications. MMC 4.0 transfer rates can
be up to 48MHz. SDIO 1.1 supports transfer rates of up to 24MHz. The US15W SDIO/MMC controller
supports only flash cards using byte addressing limiting the maximum memory density to 2GB; sector
based addressing is not supported.
Module power supply
The PROTEUS module supports a wide input voltage range from +8.5V to +24V DC with a nominal
operating voltage of +12V. Over current and over voltage protection are provided on these main input
rails. In the COM Express implementation an addi5V standby rail is available with an input
voltage range from 4.75V to 5.25V. Applications requiring Real Time Clock (RTC) backup support
have the option of fitting a lithium battery or using a SuperCap. In standalone operation the power
supply input is via a PCB mounted connector and via the 220-pin COM Express connector in the COM
Express primary configuration.
Indicator LEDs
Indicator LEDs are provided on the module to indicate:
•
PCIE express minicard slot 0 activity.
•
PCIE express minicard slot 1 activity.
•
Bluetooth activity.
•
Micro SD card activity.
•
Power states S0, S3 and S5.
•
Additional dual state on board edge LED indicates sleep state (orange), full power (green) and
HD/SD activity (green flashing).
