ADLINK Technology nanoX-AL, Руководство пользователя

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Module Interfaces
4.5. Switch Settings
Switch Locations
Figure 5: cExpress Switch Locations
BIOS Select and Mode Configuration Switch
Module has two BIOS chips and BIOS operation can be configured to "PICMG" and "Failsafe" modes using BSW1,
Pin 2. (name of this swtich on circuit is BSW1)
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 (BSW1 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
Table 5: BIOS Select and Mode Configuration Switch Settings
Note:
The switch can be removed and 0 ohm used to support all configurations above by project basis.
BIOS Select and Mode
Configuration Switch