Xycom 1341, Руководство пользователя

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1341 Embedded Node PC Appendix B – Technical Specifications
There are three steps to complete the configuration setup:
(1) Enter the MB PnP Mode; (2) Modify the data of configuration registers; (3) Exit the MB PnP Mode.
Undesired result may occur if the MB PnP Mode is not exited normally.
(1) Enter the MB PnP Mode
To enter the MB PnP Mode, four special I/O write operations are to be performed during Wait for Key
state. To ensure the initial state of the key-check logic, it is necessary to perform four write opera-tions to
the Special Address port (2EH). Two different enter keys are provided to select configuration ports
(2Eh/2Fh) of the next step.
(2) Modify the Data of the Registers
All configuration registers can be accessed after entering the MB PnP Mode. Before accessing a selected
register, the content of Index 07h must be changed to the LDN to which the register belongs, except some
Global registers.
(3) Exit the MB PnP Mode
Set bit 1 of the configure control register (Index=02h) to 1 to exit the MB PnP Mode.