Method to Provide Asynchronous Redirection for the Ibm RT-PC
Original Publication Date: 1987-May-01
Included in the Prior Art Database: 2005-Feb-01
A PC application running on a 80286 co-processor card on certain models of RT-PC cannot perform asynchronous I/O without a serial/parallel adapter card installed in the machine. The new method provides a translation function which redirects asynchronous I/O between the 80286 co-processor and the asynchronous serial ports on the native planar (Zilog 8530 processor) instead of to the serial/parallel adapter. The two serial asynchronous ports on the planar may be used for serial asynchronous I/O by translating all commands and data to the 8530 processor format. This allows the customer to run PC applications without purchasing a serial/parallel adapter. The figure illustrates where I/O, which would normally go to the serial/parallel adapter, is trapped by the hardware on the co-processor card.