Hardware reference guide

Chapter 2: The Hardware
Imaging Scanners
10
7535 Hardware Reference Guide
cessor. Activation of the scanner trigger(s) or the keyboard scan button(s) will ini-
tiate a scan with the appropriate scanner. The decoded scan driver is responsible for
receiving scan data and passing it to the Scan Control Service.
2.3.4 Imaging Scanners
The 7535 can support an imaging scanner; both internal and external imaging scan-
ners are supported. Psion Teklogix provides a driver for this scanner.
2.4 The Display
The 7535 is available with a 240x320-pixel display, either monochrome (64 shades
of grey) or colour (256k colours). The contrast of the display can be adjusted from
the keyboard via hot-keys, and is automatically temperature-compensated.
2.4.1 Touch Input
Touch input is an option for the 7535’s display. The touch driver controls the hard-
ware directly to receive touch-down, touch-up, and movement events. Touch events
are passed to the application via the operating system.
2.4.2 The Display Backlight
The 7535 has a backlight behind its display. This backlight can be adjusted for inten-
sity, and can be configured to turn on when the ambient light level drops below a
configured value.
2.5 The Keyboard
The 7535 has two types of available keyboard layouts. One type has 58 keys; the
other has 36 keys.
Windows CE .NET returns ‘virtual key codes’ for keypresses. Psion Teklogix’ key-
board drivers take into account when Psion Teklogix’ own special modifier keys
(such as the Blue or Orange key) are pressed; the keyboard driver provides the
virtual key code of the modified key.