Psion Teklogix OMNii HDK XT10, Руководство пользователя

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Chapter 2: Getting Started
Expansion Device Requirements
Psion Teklogix Omnii HDK User Manual 13
2.4 Expansion Device Requirements
2.4.1 Device EEPROM
It is highly recommended that any expansion device attached to an Omnii expansion port be
equipped with a Maxim DS2431 EEPROM. This 1-wire EEPROM is used to store specific data
that identifies the expansion device to Omnii. On boot-up, Omnii reads the EEPROM of all
devices attached to the expansion ports, and searches for corresponding entries in the registry that
specify the device driver(s) and port configuration to use for that device.
Details on this EEPROM can be found in Chapter 8: “EEPROM Specifications”, and instructions
on reading and writing the EEPROM using the HDK Demo application can be found in
Section 10.6.2.4: “EEPROM”.
2.4.2 Device Registry Keys
For each expansion device, certain registry keys and values must be added to the Omnii registry.
These registry keys provide Omnii with the information needed to load the required device
driver(s) and to configure the data pins of the expansion port appropriately.
Details on these registry keys can be found in Section 4.4: “Registry Keys”, and specific examples
are given in Section 10.4: “Creating Registry Keys”.