| 摘要 |
A computer system includes a software UART emulation and uses standard operating system protocols to minimized the chance of I/O conflicts between a serial device having a UART and a non-standard serial device which communicates through the UART emulation. A COM driver which can replace a standard COM driver in an operating environment such as provided by Microsoft WINDOWS TM contains the UART emulation. The COM driver can also include a software modem that is accessed through the UART emulation in the same manner as a modem having a hardware UART. The COM driver also sets the device address of the non-standard device on an ISA bus by determining the device addresses of COM port I/O slots used by UARTs, sending a predetermined pattern on the ISA bus to indicate a device address is to come, and then sending a value indicating a device address not used by the UARTs. The pattern has a length sufficient to make inadvertent generation of the pattern unlikely. The non-standard device recognizes the predetermined pattern and selects a device address according to the value from the COM driver.
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