S u b C o m p a c t B o a r d
A E C - 6 6 3 8
Appendix A Programming the Watchdog Timer
A-3
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
Write exit key 0xAA to the index port.
Summary of Contents for AEC-6638
Page 35: ...Embedded Controller A E C 6 6 3 8 Chapter 3 AMI BIOS Setup 3 1 AMI BIOS Setup Chapter 3...
Page 76: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 1 I O Information Appendix B...
Page 77: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 2 B 1 I O Address Map...
Page 78: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 3...
Page 79: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 4 B 2 Memory Address Map...
Page 80: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 5 B 3 IRQ Mapping Chart...
Page 81: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 6...
Page 82: ...Embedded Controller A E C 6 6 3 8 Appendix B I O Information B 7 B 4 DMA Channel Assignments...
