Psion Teklogix OMNii HDK XT10, User Manual

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Chapter 4: Software
Overview
Psion Teklogix Omnii HDK User Manual 25
4.1 Overview
This chapter describes the software aspects of controlling expansion modules for Omnii.
4.2 Drivers
4.2.1 Windows Drivers
The Peripherals Driver
Psion Teklogix provides the peripherals driver for all expansion and docking peripherals. The
peripherals driver is a stream driver activated very early at boot up time.
The Serial Port Driver
The full-function UART (Universal Asynchronous Receiver/Transmitter) serial port driver is
loaded if required, as determined by the registry settings for any expansion devices detected. For
details on the registry settings, see Section 4.4.1 on page 26.
4.2.2 Non-Psion Teklogix Drivers
The Psion Teklogix platform loads some standard device drivers. If the expansion module uses
standard drivers such as serial or USB, there is no need to load custom drivers.
There must be a registry entry for the driver and its parameters. For details see Section 4.4:
“Registry Keys”.
4.3 System Initialization
During system startup on Omnii, the following sequence occurs:
1. The expansion module EEPROMs are initialized and read.
2. If the registry entry for a detected expansion device indicates it is a serial device, the
full-function UART (FFUART) serial port driver is loaded and activated.
3. If the USB flag is set in the registry entry for a detected expansion device, the USB hub
is activated.
4. All drivers are identified from the EEPROM data and activated. For more details see
Section 4.4.1: “Registry Settings for Expansion Devices”.