Adapter with FIFO and buffers for interfacing a handheld scanner to the parallel printer port of a portable computer

摘要

An adapter system is used to interface a handheld scanner to the parallel printer port of a portable computer and includes a data buffer to receive serial video data from the handheld scanner and to convert the serial video data into parallel video data. A scanner resolution latch receives scanner controller signals from the handheld scanner and provides scanning resolution data to a printer control and status bus of the printer port. A memory unit is used to store the parallel video data from the data buffer and to provide the parallel video data to the printer control and status bus. A memory controller receives the scanner controller signals and generates write signals to the memory unit so as to enable the memory unit to store the parallel video data therein. The memory controller further generates an interrupt signal at the printer control and status bus so as to inform the computer that video data is available when a predetermined quantity of the parallel video data has been stored in the memory unit.