Kontron COMe-mCT10, User Manual

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4.4 Serial Peripheral Interface (SPI)
The Serial Peripheral Interface Bus or SPI bus is a synchronous serial data link standard named by Motorola that operates
in full duplex mode. Devices communicate in master/slave mode where the master device initiates the data frame.
Multiple slave devices are allowed with individual slave select (chip select) lines. Sometimes SPI is called a “four wire”
serial bus, contrasting with three, two, and one wire serial buses.
The SPI interface can only be used with a SPI flash device to boot from external BIOS on the
baseboard.
4.5 SPI boot
The COMe-mCT10 supports boot from an external SPI Flash. It can be configured by pin A34 (BIOS_DIS#0) and pin B88
(BIOS_DIS1#) in following configuration:
BIOS_DIS0# BIOS_DIS1# Function
open open Boot on-module BIOS
GND open Boot baseboard LPC FWH
open GND Baseboard SPI = Boot Device 1, on-module SPI = Boot
Device 2
GND GND Baseboard SPI = Boot Device 2, on-module SPI = Boot
Device 1
Using an external SPI flash
To programm an external SPI flash follow these steps:
» Connect a SPI flash with correct size (similar to BIOS ROM file size) to the module SPI interface
» Open pin A34 and B88 to boot from the module BIOS
» Boot the module to DOS with access to the BIOS image and Firmware Update Utility provided on EMD Customer
Section
» Connect pin B88 (BIOS_DIS1#) to ground to enable the external SPI flash
» Execute Flash.bat to flash the complete BIOS image to the external SPI flash
» reboot
Your module will now boot from the external SPI flash when BIOS_DIS1# is grounded.
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