Abstract: A thermostatically controlled enclosure for a small computer device includes a housing and a control circuit connected to a temperature signal generator such as a transistor. A circulating fan controlled by the output of the control circuit is mounted to the housing. Also provided is an LED indicator or audible alarm responsive to an over temperature condition within the housing. The control circuit consists of six basic blocks: a temperature to voltage converter; a high current operational amplifier; a fan on/off control; an over temperature sensor network an oscillator; and an LED or alarm driver.

Abstract: A connector for use with peripheral devices connected to computer systems via a bus includes protection circuitry for protecting the bus signal lines from unwanted signals, thus allowing a peripheral device to be connected to or disconnected from the bus without removing power from either the computer system or the bus. The connector also provides circuitry for detecting a bus free condition (i.e., no data is being transmitted over the bus), and circuitry for releasing the protection circuitry only after said bus free condition is detected. After the protection circuitry is released, the connector maintains normal signal levels such that the peripheral device may communicate with other devices on the bus. The connector also provides an indicator that it is safe or not safe to connect or disconnect a peripheral from the powered bus. The connector also includes circuitry which, when coupled to the bus, provides active termination in accordance with the SCSI bus protocol.