IBASE Technology ET976, Design Manual

Page: 54 / 93

48 COM Express® Carrier Board Design Guide
2.13 Serial Peripheral Interface Bus
2.13.1 Signal Definition
Table 13: SPI Signal Definition
Signal Pin Description I/O
SPI_CS# B97
Chip select for Carrier Board SPI – may be sourced
from chipset SPI0 or SPI1
O CMOS –
3.3V Suspend
SPI_MISO A92 Data in to Module from Carrier SPI I CMOS –
3.3V Suspend
SPI_MOSI A95 Data out from Module to Carrier SPI O CMOS –
3.3V Suspend
SPI_CLK A94 Clock from Module to Carrier SPI O CMOS –
3.3V Suspend
SPI_POWER A91 Power supply for Carrier Board SPI – sourced from
Module – nominally 3.3V. The Module shall provide a
minimum of 100mA on SPI_POWER.
Carriers shall use less than 100mA of SPI_POWER.
SPI_POWER shall only be used to power SPI devices
on the Carrier. O – 3.3V
Suspend
BIOS_DIS0# A34 Selection strap to determine the BIOS boot device.
The Carrier should only float these or pull them low,
please refer to for strapping options of BIOS disable
signals. I CMOS
BIOS_DIS1# B88 Selection strap to determine the BIOS boot device.
The Carrier should only float these or pull them low,
Effect of the BIOS disable signals on page 119
IPICMG COM Express Carrier Board Design Guide,
Rev. 20 / December 6, 2013) for strapping options
of BIOS disable signals. I CMOS