METHOD OF GENERATING CLOCK OF I/O CARD OF PERSONAL COMPUTER

摘要

PURPOSE: To eliminate the need of an independent crystal oscillator and to reduce the cost by inputting a main board clock from a personal computer, processing the main board clock and making it into a control clock having a frequency which is preset. CONSTITUTION: An I/O card 30 is provided with a connector 31 inserted into the slot of a main board in the personal computer, a UART (general-purpose asynchronous transmitter/receiver) circuit 32 receiving and transmitting a data bit and a frequency division circuit 33, The clock is directly impressed on the I/O card 30 from the main board of the personal computer. The clock of the main board is processed into the desired clock for UART circuit 32 of the I/O card 30 in the division circuit 33. The desired clock is inputted to the UART circuit 32 of the I/O card 30. Thus, the clock in the I/O card 30 can be generated without using the independent crystal oscillator.