OEMs have a variety of hardware options when building H/PCs. An H/PC includes the following hardware options:
Windows CE 2.0 supports an LCD with a resolution of 480 x 240, or higher in landscape orientation. The screen can have a color resolution of 2, 4, or 8 bits per pixel (bpp), and can also use 3–3–2 mode. The pixel arrangement renders the display in black and white, grayscale, or 256 colors.
Windows CE 2.10 can also support a 640 x 480 or 800 x 600 pixel resolution and a dot pitch of either .24, .26, or .28. It can also support 8, 16, 24, or 32 bpp.
Windows CE 2.0 supports a resistive touch panel covering the screen. The touch panel enables the screen to work like a mouse on a desktop computer. Tapping the touch screen sends the same kind of messages that clicking with the left mouse button does on a desktop computer. The user can also select and drag items. In order to sense quick changes in user input, the touch screen has a refresh rate of at least 100 samples per second. Because most H/PCs have no mouse, cursor support is limited to a spinning hourglass used as a wait cursor. You cannot change the shape of the cursor to indicate an active target, such as a hyperlink.
Windows CE 2.10 supports pointing devices. Some H/PCs may include a pointing device as an alternative to a touch panel.
Windows CE 2.10 supports pointing technology. Many devices running Windows CE 2.10 contain a touch panel. However, some OEMs may choose to implement a mouse, trackball, or an eraser pointer device, instead. An H/PC with an alternative pointing device supports various types of cursors.
Windows CE 2.0 supports a QWERTY keyboard with some keys omitted. QWERTY is the standard English-language keyboard layout named for the six leftmost characters in the top row of alphabetical characters. An H/PC keyboard includes a CTRL key, an ALT key, and two SHIFT keys. Infrequently used keys, such as PRINT SCREEN and SCROLL LOCK, are not included. The keyboard supports separate key-down and key-up events.
Windows CE 2.10 supports a keyboard with half-travel, near-regular size keys. Windows CE 2.10 also includes support for function keys. However, some hardware solutions, such as the tablet-style H/PC, do not necessarily come with a keyboard. An OEM may choose to install a slide-out keyboard or an external keyboard. Alternately, the tablet style may incorporate software input panel technology, such as that found on a Palm-size PC.
Windows CE 2.0 supports a microphone. This support requires 16-bit sampling at 8 kHz, while a codec compresses the recording to 2.4 kilobits per second (Kbps). The codec is identical to a desktop computer audio compression manager (ACM). Some OEMs may add a microphone jack to the hardware for an external microphone. The jack is transparent to the software.
You can use the built-in speakers to play a variety of sounds, such as notification events, voice recordings, or other .wav files. In addition, you can use the speakers like a pager for notification or for dual-tone multifrequency (DTMF) dialing output. Some OEMs may add a headphone jack for headphones, external speakers, or other audio-out hardware. This jack is transparent to the software.
The most common notification option for an H/PC is the external LED. This flashing light provides a simple, low-power reminder for the user. Windows CE 2.0 supports a notification button. This button lets a user acknowledge notifications without having to open the H/PC. The notification button is often incorporated into the notification LED. Another notification option is a silent buzzer.
An H/PC can run at least 10 hours on its main battery source. An H/PC also has a backup battery to avoid data loss when a user changes the main battery. Later versions of H/PC hardware include rechargeable battery packs, rather than AA alkaline batteries, and include an external port for alternating current (AC).
Windows CE 2.0 supports the following chip sets:
Windows CE 2.10 supports the following chip sets:
Note A MIPS processor has a lower code density than comparable processors. Consequently, a device with a MIPS microprocessor usually has more ROM than comparable devices with another chip set. A device with a MIPS microprocessor alsouses more memory for running applications.
The following table describes the minimum RAM and ROM required for software running on an H/PC.
Handheld PC software |
RAM |
ROM |
| Microsoft® Windows® CE for the Handheld PC | 8 MB | 4 MB |
| Microsoft® Windows® CE, Handheld PC Edition, version 3.0 | 8 MB | 16 MB |
| Microsoft® Windows® CE, Handheld PC Professional Edition, version 3.0 | 8 MB | 16 MB |
Windows CE supports additional RAM. An OEM may also choose to add additional ROM. Additional ROM may be necessary, depending on the the CPU used, the components that the OEM includes with a custom operating system (OS, and the number of components compressed in ROM.
Because it is important to conserve memory, an OEM may compress some components of the software for an H/PC into ROM. When a user needs a component, the operating system decompresses that component and transfers it to RAM. Because of this transfer, compressed files slow performance. This effect is usually more pronounced on MIPS processors.
OEMs may choose to add mass storage devices for storing database files, documents, and other large pieces of information. Due to power constraints, the most common mass storage devices are the Iomega Click! drive, the PC Card, and CompactFlash.
The Click! drive contains a removable 40-MB disk that is approximately 3 mm thick and 2 inches square.
PC Card slots are a common option for an H/PC. A PC Card slot can be used for internal modems, one-way pagers, and other peripherals. In addition to standard PC Card slot capabilities, a PC Card can programmatically request power from a PC Card slot. An H/PC can also receive interrupts from PC Cards, even if the H/PC is in suspended mode. Because Windows CE supports only a portion of the Personal Computer Memory Card International Association (PCMCIA) standard, not all peripherals are supported. However, because Windows CE supports installable device drivers, third-party software and hardware vendors can add support for additional devices by providing device drivers that you can install into RAM on an H/PC.
A Compact Flash slot can be used for additional storage cards, Ethernet cards, bar code readers, modems, and other peripherals. Like PC Card slots, Compact Flash slots support sending interrupts and can request power from an H/PC.
The built-in, nine-pin serial port on an H/PC operates identically to an RS232-compliant serial port on a desktop computer. Applications use the serial port for communications between an H/PC and other hardware. An H/PC can connect to a desktop computer, using a serial cable or optional docking cradle that is connected to the computer. A cradle is available from many H/PC manufacturers. The serial port can be used as a printer port, as well. Windows CE 2.10 supports a serial port universal asynchronous receiver-transmitter (UART) and a maximum transmission speed of 115 kBps. However, an OEM can include a faster serial port.
The infrared (IR) port on an H/PC supports Point-to-Point Protocol (PPP) serial connections with any hardware that is compliant with Infrared Data Association (IrDA) standards, such as a desktop computer or another Windows CE–based platform. The IR port also supports printers that are IR-enabled and those with parallel interfaces.
You can establish connections between two IrDA-compliant devices that have ports aligned within 15 degrees of each other. They must also be no more than 3 feet apart. IrDA specifications provide for serial IR links operating at speeds up to 115.2 KBps. Windows CE 2.10 supports Fast IR.
Windows CE 2.10 supports a USB host, which allows an H/PC to use USB peripherals. An H/PC requires OEM-supplied drivers for any USB peripheral device that the OEM supports.
In order to free the PC Card slot for other uses, many H/PCs contain an internal modem. Windows CE 2.10 supports modems that operate at a speed of at least 28.8 kBps and have their own UART.
The VGA-out port connects an H/PC to a VGA monitor. The port supports a minimum resolution of 640 x 480. This port can transmit data that is not seen on an H/PC user’s display. For example, the Handheld Pro Edition software can display a slide created with the Microsoft® Pocket PowerPoint® presentation graphics program through the VGA-out port, while displaying a document created with the Microsoft® Pocket Word word processor on an H/PC user’s screen.
For more information about H/PC hardware, see the Microsoft Windows CE Web site at http://www.microsoft.com/windowsce.