Lenovo PC 300PL Technical Information Manual 6562, 6592 - Page 25

Chapter 2. System Board Features Infrared Port An optional infrared port can be added to PC 300PL computers. To do this, an internal cable/connector assembly must be attached to the infrared header provided on the system board. This assembly provides a female, 9-pin, D-shell connector to be located in the knockout area at the rear of the computer. An infrared module (which contains the infrared optics) attaches to the female connector via a shielded cable with a standard 9-pin, male, D-shell connector. The internal cable/connector assembly and the infrared module/shielded cable do not come standard with PC 300PL computers. They can be purchased from IBM or an IBM reseller as a single option package (referred to as the 4.0 MBit IR Transceiver Option). Once the infrared option is installed, the infrared function must be enabled by configuring UART2 to infrared mode, rather than normal mode. (Note that UART2 can be used as either an infrared port or a second serial port; it cannot be used for both purposes.) The infrared port uses any of the same four system resource assignments as the serial port. The software required for infrared communication is available on the Ready-to-Configure CD that comes with PC 300PL computers. Note: For Windows 95, an infrared device driver must be installed. The device driver can be downloaded from the Microsoft Windows 95 Updates World Wide Web site. The infrared module is capable of establishing a link of up to one meter (3.3 ft.) at a rate of 115 kilobits-per-second (Kbps). The infrared interface complies with HP-SIR, SHARP-IR and IrDA-2. For information on connector pin assignments for the infrared port, refer to "Infrared Port Connector (Optional)" on page 47. Keyboard and Mouse Ports The keyboard-and-mouse subsystem is controlled by a general purpose, 8-bit microcontroller. The controller consists of 256 bytes of data memory and 2 KB of read-only memory (ROM). The controller has two logical devices; one controls the keyboard, and the other controls the mouse. The keyboard has two fixed I/O addresses and a fixed IRQ line (IRQ1). The keyboard can operate without a companion mouse, but the mouse can only operate with its companion keyboard. The mouse has a fixed IRQ line (IRQ12), but it does not have its own I/O address; it relies on the addresses used by the keyboard. The following table shows the typical system resource assignments for the keyboard and mouse. Table 5. System Resource Assignments for the Keyboard and Mouse Configuration ROM RAM I/O Address (Hex) Keyboard & mouse None None 0060, 0064 Keyboard only Mouse only None None None None 0060, 0064 0060, 0064 IRQ 1 (keyboard) 12 (mouse) 1 12 DMA None None None Note: Keyboard & mouse is the default. When the computer is started, the resource assignments are subject to change during POST. For an external interface, the keyboard and mouse each have a 6-pin connector. For information on connector pin assignments, see "Keyboard and Mouse Port Connectors" on page 48. Chapter 2. System Board Features 13