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OSD3358-SM-RED
– User Guide
Rev. 1.0 9/19/2017
Octavo Systems LLC
Copyright 2017
3.16
NOR flash (U21)
A 128MB Serial NOR Flash U21 (shown below) is connected to the processor via SPI0. This
non-volatile storage space can be utilized by applications running on the processor when
needed and can also be used for secure boot in conjunction with the TPM. The SPI0 serial
interface used to communicate with the Flash is multiplexed with the I2C1 and UART2
interfaces on header J6. When using the NOR Flash, the 2 pins of the jumper J11 should be
shorted together or the FLASH_EN signal controlled by the processor should be pulled high.
This will disable the use of the I2C1 and UART2 interfaces through J6. If the Flash is not used,
the pins of the jumper J11 must not be populated in order to use the I2C1 and UART2 interfaces
of the processor through header J6.
Figure 36: NOR flash on board
NOR flash S25FL127S datasheet:
http://www.cypress.com/file/177961/download
