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nanoX-BT
4.5.
Switch Settings
4.5.1.
Switch Locations
4.5.2.
SW1: BIOS Select and Mode Configuration Switch
Module has two BIOS chips and BIOS operation can be configured to "PICMG" and "Failsafe" modes using SW1, Pin 2.
Setting the module to PICMG mode will configure the BIOS chips on the module as SPI0 and SPI1. In PICMG mode, a BIOS chip CANNOT
be placed in SPI0 on the carrier.
In dual-BIOS Failsafe mode, both BIOS chips on the module are configured as SPI1. Only one of the two is connected to the SPI bus at any
given time. In case of BIOS failure of the primary SPI1 BIOS, the system will reboot and switch to the secondary SPI1 BIOS on the module.
In Failsafe mode, it is allowed to also have an SPI0 BIOS on the carrier.
In both modes, strapping can select whether to boot from SPI0 or SPI1 (SW1 Pin 1).
Mode
Pin 1
Pin 2
Boot from SPI0 (Default)
On
—
Boot from SPI1
Off
—
Set BIOS to PICMG mode
—
On
Set BIOS to Failsafe BIOS mode (Default)
—
Off
SW1
